├── .gitignore
├── C++
    ├── #deleteDuplicatesii.cpp#
    ├── 3sum.cpp
    ├── addTwoNumber.cpp
    ├── arrange.cpp
    ├── atoi.cpp
    ├── binarySearch.cpp
    ├── braces.cpp
    ├── compareNum.cpp
    ├── convert.cpp
    ├── convertToTitle.cpp
    ├── coverPoints.cpp
    ├── deleteDuplicatesi.cpp
    ├── deleteDuplicatesii.cpp
    ├── detectCycle.cpp
    ├── diagonal.cpp
    ├── duplicate.cpp
    ├── evalRPN.cpp
    ├── findCount.cpp
    ├── findMin.cpp
    ├── gcd.cpp
    ├── generateMatrix.cpp
    ├── generatePascal.cpp
    ├── getIntersectionNode.cpp
    ├── intersect.cpp
    ├── isPalindrome.cpp
    ├── isPower.cpp
    ├── largestNum.cpp
    ├── lengthofLastWord.cpp
    ├── listPalindrome.cpp
    ├── longestCommonPrefix.cpp
    ├── longestPalindrome.cpp
    ├── maxArea.cpp
    ├── maxSet.cpp
    ├── maxSubArray.cpp
    ├── mergeIntervals.cpp
    ├── mergeTwoLists.cpp
    ├── minStack.cpp
    ├── numSetBits.cpp
    ├── partition.cpp
    ├── pow.cpp
    ├── prevSmaller.cpp
    ├── primeSum.cpp
    ├── removeNthFromEnd.cpp
    ├── reorderList.cpp
    ├── repeatedNum.cpp
    ├── reverse.cpp
    ├── reverseBetween.cpp
    ├── roman2int.cpp
    ├── rotate.cpp
    ├── rotateRight.cpp
    ├── rotatedsearch.cpp
    ├── searchInsert.cpp
    ├── searchMatrix.cpp
    ├── setMatrixZeros.cpp
    ├── singleNumberi.cpp
    ├── singleNumberii.cpp
    ├── sqrt.cpp
    ├── substr.cpp
    ├── swapColor.cpp
    ├── titleToNumber.cpp
    ├── trailingZeros.cpp
    ├── uniquePaths.cpp
    └── wave.cpp
├── LICENSE
├── Python
    ├── __init__.py
    ├── addTwoNumbers.py
    ├── addone.py
    ├── arrange.py
    ├── convertToTitle.py
    ├── detectCycle.py
    ├── flip.py
    ├── gcd.py
    ├── generateMatrix.py
    ├── generatePascal.py
    ├── getRow.py
    ├── isPalindrome.py
    ├── isPower.py
    ├── maxSet.py
    ├── nextPermutation.py
    ├── partition.py
    ├── primeSum.py
    ├── reorderList.py
    ├── reverse.py
    ├── titleToNumber.py
    ├── trailingZeros.py
    └── uniquePaths.py
├── README.md
├── README.org
├── img
    └── ib-logo-square.png
├── repeatedNumber.py
└── timeComplexity.md


/.gitignore:
--------------------------------------------------------------------------------
1 | .idea
2 | /Python/__init__.py


--------------------------------------------------------------------------------
/C++/#deleteDuplicatesii.cpp#:
--------------------------------------------------------------------------------
 1 | ListNode* Solution::deleteDuplicates(ListNode *head) {
 2 |   if (head == NULL) return NULL;
 3 |   ListNode* fakeHead = new ListNode(0);
 4 |   fakeHead->next = head;
 5 |   ListNode* pre = fakeHead;
 6 |   ListNode* cur = head;
 7 |   while (cur != NULL) {
 8 |     while (cur->next != NULL && cur->val == cur->next->val) {
 9 |       cur = cur->next;
10 |     }
11 |     if (pre->next == cur) {
12 |       pre = pre->next;
13 |     } else {
14 |       pre->next = cur->next;
15 |     }
16 |     cur = cur->next;
17 |   }
18 |   return fakeHead->next;
19 |     }
20 | 


--------------------------------------------------------------------------------
/C++/3sum.cpp:
--------------------------------------------------------------------------------
 1 | class Solution {
 2 | public:
 3 |   int threeSumClosest(vector<int> &num, int target) {
 4 |     sort(num.begin(), num.end());
 5 |     int bestSum = 1000000000, sum = 0;
 6 |     // Fix the smallest number in the three integers
 7 |     for (int i = 0; i < num.size() - 2; i++) {
 8 |       // Now num[i] is the smallest number in the three integers in the solution
 9 |       int ptr1 = i + 1, ptr2 = num.size() - 1;
10 |       while (ptr1 < ptr2) {
11 |         sum = num[i] + num[ptr1] + num[ptr2];
12 |         if (abs(target - sum) < abs(target - bestSum)) {
13 |           bestSum = sum;
14 |         }
15 |         if (sum > target) {
16 |           ptr2--;
17 |         } else {
18 |           ptr1++;
19 |         }
20 |       }
21 |     }
22 |     return bestSum;
23 |   }
24 | };
25 | 


--------------------------------------------------------------------------------
/C++/addTwoNumber.cpp:
--------------------------------------------------------------------------------
 1 | class Solution {
 2 | public:
 3 |   ListNode *addTwoNumbers(ListNode *l1, ListNode *l2) {
 4 |     if(!l1)
 5 |       return l2;
 6 |     if(!l2)
 7 |       return l1;
 8 | 
 9 |     int carry = (l1->val + l2->val) / 10;
10 |     ListNode *l3 = new ListNode((l1->val + l2->val) % 10);
11 |     ListNode *tail = l3;
12 |     l1 = l1->next;
13 |     l2 = l2->next;
14 | 
15 |     while(l1 || l2 || carry)
16 |       {
17 |         int sum = ((l1 ? l1->val : 0) + (l2 ? l2->val : 0) + carry);
18 |         ListNode *t  = new ListNode(sum % 10);
19 |         carry = sum / 10;                                          
20 | 
21 |         if(l1)
22 |           l1 = l1->next;
23 |         if(l2)
24 |           l2 = l2->next;
25 |         tail->next = t;
26 |         tail = t;
27 |       }
28 | 
29 |     return l3;
30 |   }
31 | };
32 | 


--------------------------------------------------------------------------------
/C++/arrange.cpp:
--------------------------------------------------------------------------------
 1 | void Solution::arrange(vector<int> &Vec) {
 2 |     // Do not write main() function.
 3 |     // Do not read input, instead use the arguments to the function.
 4 |     // Do not print the output, instead return values as specified
 5 |     // Still have a doubt. Checkout www.interviewbit.com/pages/sample_codes/ for more details
 6 |     int N = Vec.size();
 7 |     for(int i = 0; i < N; ++i) {
 8 |         Vec[i] = Vec[i] + (Vec[Vec[i]]%N) * N;
 9 |     }
10 | 
11 |     for(int i = 0; i < N; ++i) {
12 |         Vec[i] = Vec[i] / N;
13 |     }
14 | }
15 | 


--------------------------------------------------------------------------------
/C++/atoi.cpp:
--------------------------------------------------------------------------------
 1 | class Solution {
 2 | public:
 3 |   int atoi(const string &str) {
 4 |     int sign = 1, base = 0, i = 0;
 5 |     while (str[i] == ' ') { i++; }
 6 |     if (str[i] == '-' || str[i] == '+') {
 7 |       sign = (str[i++] == '-') ? -1 : 1;
 8 |     }
 9 |     while (str[i] >= '0' && str[i] <= '9') {
10 |       if (base >  INT_MAX / 10 || (base == INT_MAX / 10 && str[i] - '0' > 7)) {
11 |         if (sign == 1) return INT_MAX;
12 |         else return INT_MIN;
13 |       }
14 |       base  = 10 * base + (str[i++] - '0');
15 |     }
16 |     return base * sign;
17 |   }
18 | };
19 | 


--------------------------------------------------------------------------------
/C++/binarySearch.cpp:
--------------------------------------------------------------------------------
 1 | #include <stdio.h>
 2 | #include <iostream>
 3 | 
 4 | int binarySearch(int A[], int n, int x)
 5 | {
 6 |   int low = 0, high = n-1;
 7 |   while(low <= high){
 8 |     int mid = (low+high)/2;
 9 |     if(x == A[mid])
10 |       return mid;
11 |     else if(x < A[mid])
12 |       high = mid - 1;
13 |     else
14 |       low = mid + 1;
15 |   }
16 |   return -1;
17 | }
18 | 
19 | int main()
20 | {
21 |   int A[] = {2,4,5,7,13,14,15,23};
22 |   std::cout << "Enter a number: ";
23 |   int x;
24 |   std::cin >> x;
25 |   int index = binarySearch(A,8,x);
26 |   if(index != -1)
27 |     std::cout << "Number " << x << " is at index " << index << std::endl;
28 |   else
29 |     std::cout << "Number " << x <<  " not found" << std::endl;
30 | }
31 | 


--------------------------------------------------------------------------------
/C++/braces.cpp:
--------------------------------------------------------------------------------
 1 | int braces(string str)
 2 | {
 3 |   stack<char> Stack;
 4 | 
 5 |   for(int i = 0; i < str.size(); ++i) {
 6 |     if(str[i] == ')') {
 7 |       int count = 0;
 8 |       while(Stack.top() != '(') {
 9 |         Stack.pop();
10 |         count++;
11 |       }
12 |       Stack.pop();
13 |       if(count < 2)
14 |         return 1;
15 |     } else {
16 |       Stack.push(str[i]);
17 |     }
18 |   }
19 | 
20 |   bool redundant = true;
21 | 
22 |   while(Stack.size()) {
23 |     if(Stack.top() == '(' || Stack.top() == ')') {
24 |       redundant = false;
25 |       break;
26 |     }
27 |     Stack.pop();
28 |   }
29 | 
30 |   if(!redundant)
31 |     return 1;
32 |   return 0;
33 | }
34 | };
35 | 


--------------------------------------------------------------------------------
/C++/compareNum.cpp:
--------------------------------------------------------------------------------
 1 | class Solution {
 2 | public:
 3 |   static bool compareNum(string a, string b) {
 4 |     return a + b > b + a;
 5 |   }
 6 | 
 7 |   string largestNumber(const vector<int> &num) {
 8 |     string result;
 9 |     vector<string> str;
10 |     for (int i = 0; i < num.size(); i++) {
11 |       str.push_back(to_string(num[i]));
12 |     }
13 |     sort(str.begin(), str.end(), compareNum);
14 |     for (int i = 0; i < str.size(); i++) {
15 |       result += str[i];
16 |     }
17 | 
18 |     int pos = 0;
19 |     while (result[pos] == '0' && pos + 1 < result.size()) pos++; 
20 |     return result.substr(pos);
21 |   }
22 | };
23 | 


--------------------------------------------------------------------------------
/C++/convert.cpp:
--------------------------------------------------------------------------------
 1 | class Solution {
 2 | public:
 3 |   string convert(string s, int nRows) {
 4 | 
 5 |     if (nRows <= 1)
 6 |       return s;
 7 | 
 8 |     const int len = (int)s.length();
 9 |     string *str = new string[nRows];
10 | 
11 |     int row = 0, step = 1;
12 |     for (int i = 0; i < len; ++i)
13 |       {
14 |         str[row].push_back(s[i]);
15 | 
16 |         if (row == 0)
17 |           step = 1;
18 |         else if (row == nRows - 1)
19 |           step = -1;
20 | 
21 |         row += step;
22 |       }
23 | 
24 |     s.clear();
25 |     for (int j = 0; j < nRows; ++j)
26 |       {
27 |         s.append(str[j]);
28 |       }
29 | 
30 |     return s;
31 |   }
32 | 
33 | };
34 | 


--------------------------------------------------------------------------------
/C++/convertToTitle.cpp:
--------------------------------------------------------------------------------
1 | string convertToTitle(int n) {
2 |     string ans;
3 |     while (n) {
4 |         ans = char ((n - 1) % 26 + 'A') + ans;
5 |         n = (n - 1) / 26;
6 |     }
7 |     return ans;
8 | }
9 | 


--------------------------------------------------------------------------------
/C++/coverPoints.cpp:
--------------------------------------------------------------------------------
 1 | // Input : X and Y co-ordinates of the points in order. 
 2 | // Each point is represented by (X[i], Y[i])
 3 | int Solution::coverPoints(vector<int> &x, vector<int> &y) {
 4 |   if (x.size() <= 1) return 0;
 5 |   assert(x.size() == y.size());
 6 |   int ans = 0;
 7 |   for (int i = 1; i < x.size(); i++) {
 8 |     ans += max(abs(x[i] - x[i-1]), abs(y[i] - y[i-1]));
 9 |   }
10 |   return ans;
11 |         }
12 | 


--------------------------------------------------------------------------------
/C++/deleteDuplicatesi.cpp:
--------------------------------------------------------------------------------
 1 | ListNode *deleteDuplicates(ListNode *head) {
 2 |   ListNode *origin = head;
 3 |   while (head != NULL) {
 4 |     while(head->next != NULL && head->val == head->next->val) {
 5 |       head->next = head->next->next;
 6 |     }
 7 |     head = head->next;
 8 |   }
 9 |   return origin;
10 | }
11 | 


--------------------------------------------------------------------------------
/C++/deleteDuplicatesii.cpp:
--------------------------------------------------------------------------------
 1 | Solution::deleteDuplicates(ListNode *head) {
 2 |   if (head == NULL) return NULL;
 3 |   ListNode* fakeHead = new ListNode(0);
 4 |   fakeHead->next = head;
 5 |   ListNode* pre = fakeHead;
 6 |   ListNode* cur = head;
 7 |   while (cur != NULL) {
 8 |     while (cur->next != NULL && cur->val == cur->next->val) {
 9 |       cur = cur->next;
10 |     }
11 |     if (pre->next == cur) {
12 |       pre = pre->next;
13 |     } else {
14 |       pre->next = cur->next;
15 |     }
16 |     cur = cur->next;
17 |   }
18 |   return fakeHead->next;
19 | }
20 | 


--------------------------------------------------------------------------------
/C++/detectCycle.cpp:
--------------------------------------------------------------------------------
 1 | class Solution {
 2 | public:
 3 |   ListNode *detectCycle(ListNode *head) {
 4 |     if (head == NULL || head->next == NULL) return NULL;
 5 | 
 6 |     ListNode* firstp = head;
 7 |     ListNode* secondp = head;
 8 |     bool isCycle = false;
 9 | 
10 |     while(firstp != NULL && secondp != NULL) {
11 |       firstp = firstp->next;
12 |       if (secondp->next == NULL) return NULL;
13 |       secondp = secondp->next->next;
14 |       if (firstp == secondp) { isCycle = true; break; }
15 |     }
16 | 
17 |     if(!isCycle) return NULL;
18 |     firstp = head;
19 |     while( firstp != secondp) {
20 |       firstp = firstp->next;
21 |       secondp = secondp->next;
22 |     }
23 | 
24 |     return firstp;
25 | 
26 |   }
27 | };
28 | 


--------------------------------------------------------------------------------
/C++/diagonal.cpp:
--------------------------------------------------------------------------------
 1 | vector<vector<int> > Solution::diagonal(vector<vector<int> > &A) {
 2 |   int i=0,j=0,x,y;
 3 |   int n=A.size();
 4 |   vector<vector<int>> v;
 5 |   vector<int> row;
 6 |   i=0;j=0;
 7 |   while(i<n){
 8 |     x=i;y=j;
 9 |     while(x<n & y>=0 ){
10 |       row.push_back(A[x][y]);
11 |       x++;y--;
12 |     }
13 |     v.push_back(row);
14 |     row.clear();
15 |     if(j<n-1)
16 |       j++;
17 |     else i++;
18 |   }
19 |   return v;
20 | }
21 | 


--------------------------------------------------------------------------------
/C++/duplicate.cpp:
--------------------------------------------------------------------------------
 1 | int Solution::repeatedNumber(const vector<int> &A) {
 2 |   // Do not write main() function.
 3 |   // Do not read input, instead use the arguments to the function.
 4 |   // Do not print the output, instead return values as specified
 5 |   // Still have a doubt. Checkout www.interviewbit.com/pages/sample_codes/ for more details
 6 |   int slow = A[0];
 7 |   int fast = A[A[0]];
 8 |   while (slow != fast) {
 9 |     slow = A[slow];
10 |     fast = A[A[fast]];
11 |   }
12 | 
13 |   fast = 0;
14 |   while (slow != fast) {
15 |     slow = A[slow];
16 |     fast = A[fast];
17 |   }
18 |   return slow;
19 | }
20 | 


--------------------------------------------------------------------------------
/C++/evalRPN.cpp:
--------------------------------------------------------------------------------
 1 | int evalRPN(vector<string> &tokens) {
 2 |             stack<int> st;
 3 |             for(int i = 0; i < tokens.size(); ++i) {
 4 |                 if(tokens[i] == "+" || tokens[i] == "-" || tokens[i] == "*" || tokens[i] == "/") {
 5 |                     int v1=st.top();
 6 |                     st.pop();
 7 |                     int v2=st.top();
 8 |                     st.pop();
 9 |                     switch(tokens[i][0]) {
10 |                         case '+':
11 |                             st.push(v2 + v1);
12 |                             break;
13 |                         case '-':
14 |                             st.push(v2 - v1);
15 |                             break;
16 |                         case '*':
17 |                             st.push(v2 * v1);
18 |                             break;
19 |                         case '/':
20 |                             st.push(v2 / v1);
21 |                             break;
22 |                     }
23 |                 } else {
24 |                     st.push(atoi(tokens[i].c_str()));
25 |                 }
26 |             }
27 |             return st.top();
28 |         }
29 | 


--------------------------------------------------------------------------------
/C++/findCount.cpp:
--------------------------------------------------------------------------------
 1 | int findCount(const vector<int> &A, int target) {
 2 |   int n = A.size();
 3 |   int i = 0, j = n - 1;
 4 |   int start = -1, end = -1;
 5 | 
 6 |   // FIND FIRST
 7 |   while (i < j)
 8 |     {
 9 |       int mid = (i + j) /2;
10 |       if (A[mid] < target) i = mid + 1;
11 |       else j = mid;
12 |     }
13 |   if (A[i] != target) return 0; // the element does not exist in the array.
14 | 
15 |   start = i;
16 | 
17 |   // FINDLAST
18 |   j = n - 1;  // We don't have to set i to 0 the second time.
19 |   while (i < j)
20 |     {
21 |       int mid = (i + j) /2 + 1;   // Make mid biased to the right
22 |       if (A[mid] > target) j = mid - 1;  
23 |       else i = mid;               // So that this won't make the search range stuck.
24 |     }
25 |   end = j;
26 |   return (end - start + 1); 
27 | }
28 | 


--------------------------------------------------------------------------------
/C++/findMin.cpp:
--------------------------------------------------------------------------------
 1 | int Solution::findMin(const vector<int> &A) {
 2 |   // Do not write main() function.
 3 |   // Do not read input, instead use the arguments to the function.
 4 |   // Do not print the output, instead return values as specified
 5 |   // Still have a doubt. Checkout www.interviewbit.com/pages/sample_codes/ for more details
 6 |   int len = A.size(),low = 0, high = len-1;
 7 |     
 8 |   while(low <= high){
 9 |     if(A[low] <= A[high]) return A[low]; //case 1
10 |     int mid = (low + high)/2;
11 |     int next = (mid+1)%len, prev = (mid+len-1)%len;
12 |     if(A[mid] <= A[next] && A[mid] <= A[prev]) //case 2
13 |       return A[mid];
14 |     else if (A[mid] <= A[high]) //case 3
15 |       high = mid - 1;
16 |     else if (A[mid] >= A[low]) //case 4
17 |       low = mid + 1;
18 |   }
19 |   return -1;
20 | }
21 | 
22 | 
23 | 
24 | 


--------------------------------------------------------------------------------
/C++/gcd.cpp:
--------------------------------------------------------------------------------
 1 | int Solution::gcd(int A, int B) {
 2 |     if(A==0)
 3 |         return B;
 4 |     else if(B==0)
 5 |         return A;
 6 |    int y=1;
 7 | 	while(y>0){
 8 | 		y=A%B;
 9 | 		A=B;
10 | 		B=y;
11 | 	}
12 | 	return A;
13 | }
14 | 


--------------------------------------------------------------------------------
/C++/generateMatrix.cpp:
--------------------------------------------------------------------------------
 1 | class Solution {
 2 | public:
 3 |   vector<vector<int> > generateMatrix(int n) {
 4 | 	int dir = 0;
 5 | 	vector< vector<int> > matrix(n, vector<int> (n, 0));
 6 | 	int i = 0, j = 0, k = 1;
 7 | 	while (k <= n * n) {
 8 | 	  matrix[i][j] = k++;
 9 | 	  if (dir == 0){
10 | 		j++;
11 | 		if (j == n || matrix[i][j] != 0) dir = 1, j--, i++;
12 | 	  } else
13 | 		if (dir == 1) {
14 | 		  i++;
15 | 		  if (i == n || matrix[i][j] != 0) dir = 2, i--, j--;
16 | 		} else
17 | 		  if (dir == 2) {
18 | 			j--;
19 | 			if (j < 0 || matrix[i][j] != 0) dir = 3, j++, i--;
20 | 		  } else
21 | 			if (dir == 3) {
22 | 			  i--;
23 | 			  if (i < 0 || matrix[i][j] != 0) dir = 0, i++, j++;
24 | 			}
25 | 	}
26 | 	return matrix;
27 |   }
28 | };
29 | 


--------------------------------------------------------------------------------
/C++/generatePascal.cpp:
--------------------------------------------------------------------------------
 1 | vector <vector<int>> Solution::generate(int A) {
 2 |     vector <vector<int>> ans;
 3 |     if (A <= 0) {
 4 |         return ans;
 5 |     }
 6 |     vector<int> temp;
 7 |     temp.push_back(1);
 8 |     ans.push_back(temp);
 9 | 
10 |     for (int r = 0; r < A - 1; r++) {
11 | 
12 |         vector<int> newRow;
13 |         newRow.push_back(1);
14 | 
15 |         for (int c = 0; c < ans[r].size() - 1; c++) {
16 |             newRow.push_back(ans[r][c] + ans[r][c + 1]);
17 |         }
18 | 
19 |         newRow.push_back(1);
20 |         ans.push_back(newRow);
21 | 
22 |     }
23 |     return ans;
24 | }
25 | 
26 | 


--------------------------------------------------------------------------------
/C++/getIntersectionNode.cpp:
--------------------------------------------------------------------------------
 1 | /**
 2 |  * Definition for singly-linked list.
 3 |  * struct ListNode {
 4 |  *     int val;
 5 |  *     ListNode *next;
 6 |  *     ListNode(int x) : val(x), next(NULL) {}
 7 |  * };
 8 |  */
 9 |  int getLength(ListNode *head) {
10 |             int ret = 0;
11 |             while (head) {
12 |                 ret++;
13 |                 head = head->next;
14 |             }
15 |             return ret;
16 |         }
17 | ListNode* Solution::getIntersectionNode(ListNode* A, ListNode* B) {
18 |             if(!A || !B)
19 |                 return NULL;
20 |             int lenA = getLength(A), lenB = getLength(B);
21 |             int lenDiff = lenA - lenB;
22 |             ListNode *pa = A;
23 |             ListNode *pb = B;
24 |             if(lenDiff > 0) {
25 |                 while(lenDiff != 0) {
26 |                     pa = pa->next;
27 |                     lenDiff--;
28 |                 }
29 |             }
30 |             else if(lenDiff < 0) {
31 |                 while(lenDiff != 0) {
32 |                     pb = pb->next;
33 |                     lenDiff++;
34 |                 }
35 |             }
36 |             while(pa && pb) {
37 |                 if(pa == pb)
38 |                     return pa;
39 |                 pa = pa->next;
40 |                 pb = pb->next;
41 |             }
42 |             return NULL;
43 |         }
44 | 


--------------------------------------------------------------------------------
/C++/intersect.cpp:
--------------------------------------------------------------------------------
 1 | vector<int> Solution::intersect(const vector<int> &A, const vector<int> &B) {
 2 |   // Do not write main() function.
 3 |   // Do not read input, instead use the arguments to the function.
 4 |   // Do not print the output, instead return values as specified
 5 |   // Still have a doubt. Checkout www.interviewbit.com/pages/sample_codes/ for more details
 6 |   vector<int> dups;
 7 |   int i = 0, j = 0;
 8 |   int n = A.size(), m = B.size();
 9 |   while(i<n && j<m){
10 |     if(A[i] == B[j]){
11 |       dups.push_back(A[i]);
12 |       i++;
13 |       j++;
14 |     }
15 |     else if (A[i]>B[j])   j++;
16 |     else
17 |       i++;
18 |   }
19 |   return dups;
20 | }
21 | 


--------------------------------------------------------------------------------
/C++/isPalindrome.cpp:
--------------------------------------------------------------------------------
 1 | bool Solution::isPalindrome(int A) {
 2 |      if(A<0)
 3 |         return false;
 4 |     int tenPow[10]={1,10,100,1000,10000,100000,1000000,10000000,100000000,1000000000};
 5 |     int i=0;
 6 |     int noOfDigits=0;
 7 |     while(i<10 && A/tenPow[i]>0) i++;
 8 |     noOfDigits=i;
 9 |     if(noOfDigits==1)
10 |         return true;
11 |     int B=A;
12 |     int C=0;
13 |     int temp;
14 |     for(i=0;i<noOfDigits;i++){
15 |         temp=B%10;
16 |         B/=10;
17 |         C+=temp*tenPow[noOfDigits-1-i];
18 |     }
19 |     if(A==C)
20 |         return true;
21 |     return false;
22 |     
23 |     
24 | }
25 | 


--------------------------------------------------------------------------------
/C++/isPower.cpp:
--------------------------------------------------------------------------------
 1 | class Solution {
 2 | public:
 3 |   bool isPower(int x) {
 4 | 	if (x <= 1) return true;
 5 | 	for (int base = 2; base < x && base < INT_MAX / base; base++) {
 6 | 	  int temp = base;
 7 | 	  while (temp <= x && temp < INT_MAX / base) {
 8 | 		temp *= base;
 9 | 		if (temp == x) return true;
10 | 	  }
11 | 	}
12 | 	return false;
13 |   }
14 | };
15 | 


--------------------------------------------------------------------------------
/C++/largestNum.cpp:
--------------------------------------------------------------------------------
 1 | class Solution {
 2 | public:
 3 |   static bool compareNum(string a, string b) {
 4 |     return a + b > b + a;
 5 |   }
 6 | 
 7 |   string largestNumber(const vector<int> &num) {
 8 |     string result;
 9 |     vector<string> str;
10 |     for (int i = 0; i < num.size(); i++) {
11 |       str.push_back(to_string(num[i]));
12 |     }
13 |     sort(str.begin(), str.end(), compareNum);
14 |     for (int i = 0; i < str.size(); i++) {
15 |       result += str[i];
16 |     }
17 | 
18 |     int pos = 0;
19 |     while (result[pos] == '0' && pos + 1 < result.size()) pos++; 
20 |     return result.substr(pos);
21 |   }
22 | };
23 | 


--------------------------------------------------------------------------------
/C++/lengthofLastWord.cpp:
--------------------------------------------------------------------------------
 1 | int lengthOfLastWord(const string &s) {
 2 |   int len = 0;
 3 |   while (*s) {
 4 |     if (*s != ' ') {
 5 |       len++;
 6 |       s++;
 7 |       continue;
 8 |     }
 9 |     s++;
10 |     if (*s && *s != ' ') len = 0;
11 |   }
12 |   return len;
13 | 
14 | }
15 | 


--------------------------------------------------------------------------------
/C++/listPalindrome.cpp:
--------------------------------------------------------------------------------
 1 | void reverse(struct ListNode** head_ref)
 2 | {
 3 |   struct ListNode* prev   = NULL;
 4 |   struct ListNode* current = *head_ref;
 5 |   struct ListNode* next;
 6 |   while (current != NULL)
 7 |     {
 8 |       next  = current->next;
 9 |       current->next = prev;
10 |       prev = current;
11 |       current = next;
12 |     }
13 |   *head_ref = prev;
14 | }
15 | 
16 | /* Function to check if two input lists have same val*/
17 | bool compareLists(struct ListNode* head1, struct ListNode *head2)
18 | {
19 |   struct ListNode* temp1 = head1;
20 |   struct ListNode* temp2 = head2;
21 | 
22 |   while (temp1 && temp2)
23 |     {
24 |       if (temp1->val == temp2->val)
25 |         {
26 |           temp1 = temp1->next;
27 |           temp2 = temp2->next;
28 |         }
29 |       else return 0;
30 |     }
31 | 
32 |   /* Both are empty reurn 1*/
33 |   if (temp1 == NULL && temp2 == NULL)
34 |     return 1;
35 | 
36 |   /* Will reach here when one is NULL
37 |      and other is not */
38 |   return 0;
39 | }
40 | 
41 | int Solution::lPalin(ListNode* A) {
42 |   struct ListNode *slow_ptr = A, *fast_ptr = A;
43 |   struct ListNode *second_half, *prev_of_slow_ptr = A;
44 |   struct ListNode *midnode = NULL;  // To handle odd size list
45 |   int res = true; // initialize result
46 | 
47 |   if (A!=NULL && A->next!=NULL) //to handle if A == 0
48 |     {
49 |       /* Get the middle of the list. Move slow_ptr by 1
50 |          and fast_ptrr by 2, slow_ptr will have the middle
51 |          ListNode */
52 |       while (fast_ptr != NULL && fast_ptr->next != NULL)
53 |         {
54 |           fast_ptr = fast_ptr->next->next;
55 | 
56 |           /*We need previous of the slow_ptr for
57 |             linked lists  with odd elements */
58 |           prev_of_slow_ptr = slow_ptr;
59 |           slow_ptr = slow_ptr->next;
60 |         }
61 | 
62 | 
63 |       /* fast_ptr would become NULL when there are even elements in list. 
64 |          And not NULL for odd elements. We need to skip the middle ListNode 
65 |          for odd case and store it somewhere so that we can restore the
66 |          original list*/
67 |       if (fast_ptr != NULL)
68 |         {
69 |           midnode = slow_ptr;
70 |           slow_ptr = slow_ptr->next;
71 |         }
72 | 
73 |       // Now reverse the second half and compare it with first half
74 |       second_half = slow_ptr;
75 |       prev_of_slow_ptr->next = NULL; // NULL terminate first half
76 |       reverse(&second_half);  // Reverse the second half
77 |       res = compareLists(A, second_half); // compare
78 | 
79 |     }
80 |   return res;
81 | }
82 | 


--------------------------------------------------------------------------------
/C++/longestCommonPrefix.cpp:
--------------------------------------------------------------------------------
 1 | string Solution::longestCommonPrefix(vector<string> &A) {
 2 |   // Do not write main() function.
 3 |   // Do not read input, instead use the arguments to the function.
 4 |   // Do not print the output, instead return values as specified
 5 |   // Still have a doubt. Checkout www.interviewbit.com/pages/sample_codes/ for more details
 6 |   if(A.empty())
 7 |     return "";
 8 |     
 9 |   for(int i = 0; i < A[0].length(); i++){
10 |     for(const auto &str : A){
11 |       if(i > str.length() || str[i] != A[0][i]){
12 |         return A[0].substr(0, i);
13 |       }
14 |     }
15 |   }
16 | }
17 | 


--------------------------------------------------------------------------------
/C++/longestPalindrome.cpp:
--------------------------------------------------------------------------------
 1 |     string preProcess(const string& s) {
 2 |         if (s.empty()) {
 3 |             return "^$";
 4 |         }
 5 |         string ret = "^";
 6 |         for (int i = 0; i < s.length(); ++i) {
 7 |             ret += "#" + s.substr(i, 1);
 8 |         }
 9 |         ret += "#$";
10 |         return ret;
11 |     }
12 | 
13 | string Solution::longestPalindrome(string s) {
14 |         string T = preProcess(s);
15 |         const int n = T.length();
16 |         vector<int> P(n);
17 |         int C = 0, R = 0;
18 |         for (int i = 1; i < n - 1; ++i) {
19 |             int i_mirror = 2 * C - i; // equals to i' = C - (i-C)
20 | 
21 |             P[i] = (R > i) ? min(R - i, P[i_mirror]) : 0;
22 | 
23 |             // Attempt to expand palindrome centered at i
24 |             while (T[i + 1 + P[i]] == T[i - 1 - P[i]]) {
25 |                 ++P[i];
26 |             }
27 | 
28 |             // If palindrome centered at i expands the past R,
29 |             // adjust center based on expanded palindrome.
30 |             if (i + P[i] > R) {
31 |                 C = i;
32 |                 R = i + P[i];
33 |             }
34 |         }
35 | 
36 |         // Find the maximum element in P.
37 |         int max_i = 0;
38 |         for (int i = 1; i < n - 1; ++i) {
39 |             if (P[i] > P[max_i]) {
40 |                 max_i = i;
41 |             }
42 |         }
43 | 
44 |         return s.substr((max_i - P[max_i]) / 2, P[max_i]);
45 |     }
46 | 


--------------------------------------------------------------------------------
/C++/maxArea.cpp:
--------------------------------------------------------------------------------
 1 | class Solution {
 2 | public:
 3 |   int maxArea(vector<int> &height) {
 4 |     int end = height.size() - 1, start = 0;
 5 |     int maxVol = 0;
 6 | 
 7 |     while(start < end)
 8 |       {
 9 |         maxVol = max(maxVol, (end - start) * min(height[start], height[end]));
10 | 
11 |         if (height[start] < height[end]) {
12 |           start++;
13 |         } else {
14 |           end--;
15 |         }
16 |       }
17 |     return maxVol;
18 |   }
19 | };
20 | Close
21 | 


--------------------------------------------------------------------------------
/C++/maxSet.cpp:
--------------------------------------------------------------------------------
 1 | vector<int> Solution::maxset(vector<int> &A) {
 2 |     // Do not write main() function.
 3 |     // Do not read input, instead use the arguments to the function.
 4 |     // Do not print the output, instead return values as specified
 5 |     // Still have a doubt. Checkout www.interviewbit.com/pages/sample_codes/ for more details
 6 |         int N = A.size();
 7 | 
 8 |         long long mx_sum = 0;
 9 |         long long cur_sum = 0;
10 |         int mx_range_left = -1;
11 |         int mx_range_right = -1;
12 |         int cur_range_left = 0;
13 |         int cur_range_right = 0;
14 | 
15 |         while(cur_range_right < N) {
16 |             if(A[cur_range_right] < 0) {
17 |                 cur_range_left = cur_range_right + 1;
18 |                 cur_sum = 0;
19 |             } else {
20 |                 cur_sum += (long long)A[cur_range_right];
21 |                 if(cur_sum > mx_sum) {
22 |                     mx_sum = cur_sum;
23 |                     mx_range_left = cur_range_left;
24 |                     mx_range_right = cur_range_right + 1;
25 |                 } else if(cur_sum == mx_sum) {
26 |                     if(cur_range_right + 1 - cur_range_left > mx_range_right - mx_range_left) {
27 |                         mx_range_left = cur_range_left;
28 |                         mx_range_right = cur_range_right + 1;
29 |                     }
30 |                 }
31 |             }
32 |             cur_range_right++;
33 |         }
34 |         vector<int> ans;
35 |         if(mx_range_left == -1 || mx_range_right == -1)
36 |                 return ans;
37 | 
38 |         for(int i = mx_range_left; i < mx_range_right; ++i)
39 |                 ans.push_back(A[i]);
40 |         return ans;
41 |     }
42 | 


--------------------------------------------------------------------------------
/C++/maxSubArray.cpp:
--------------------------------------------------------------------------------
 1 | int Solution::maxSubArray(const vector<int> &A) {
 2 |   // Do not write main() function.
 3 |   // Do not read input, instead use the arguments to the function.
 4 |   // Do not print the output, instead return values as specified
 5 |   // Still have a doubt. Checkout www.interviewbit.com/pages/sample_codes/ for more detai
 6 |   int max_so_far = A[0];
 7 |   int curr_max = A[0];
 8 |  
 9 |   for (int i = 1; i < A.size(); i++)
10 |     {
11 |       curr_max = max(A[i], curr_max+A[i]);
12 |       max_so_far = max(max_so_far, curr_max);
13 |     }
14 |   return max_so_far;
15 | }
16 | 
17 | 


--------------------------------------------------------------------------------
/C++/mergeIntervals.cpp:
--------------------------------------------------------------------------------
 1 | /**
 2 |  * Definition for an interval.
 3 |  * struct Interval {
 4 |  *     int start;
 5 |  *     int end;
 6 |  *     Interval() : start(0), end(0) {}
 7 |  *     Interval(int s, int e) : start(s), end(e) {}
 8 |  * };
 9 |  */
10 |  
11 |  /*
12 |   *This problem has a lot of corner cases which need to be handled correctly.
13 |   *Let us first talk about the approach. 
14 |   *Given all the intervals, you need to figure out the sequence of intervals which intersect with the given newInterval.
15 |   *Lets see how we check if interval 1 (a,b) intersects with interval 2 (c,d):
16 |   *Overlap case
17 |   *             a-------------------b               
18 |   *                       c------------------d
19 |   *Non overlap case :
20 |   * a--------------------b   c------------------d
21 |   *Note that if max(a,c) > min(b,d), then the intervals do not overlap. Otherwise, they overlap.
22 |   *Once we figure out the intervals ( interval[i] to interval[j] ) which overlap with newInterval, note that we can replace all the overlapping intervals with one interval which would be
23 |   *(min(interval[i].start, newInterval.start), max(interval[j].end, newInterval.end)).
24 |   */
25 | 
26 | 
27 | 
28 | vector<Interval> Solution::insert(vector<Interval> &intervals, Interval newInterval) {
29 |     // Do not write main() function.
30 |     // Do not read input, instead use the arguments to the function.
31 |     // Do not print the output, instead return values as specified
32 |     // Still have a doubt. Checkout www.interviewbit.com/pages/sample_codes/ for more details
33 |    if(newInterval.start > newInterval.end){
34 |     	int temp=newInterval.start;
35 |     	newInterval.start=newInterval.end;
36 |     	newInterval.end=temp;
37 |     }
38 | 
39 |     int i=0;
40 |     int n=intervals.size();
41 |     int p=-1,q=-1;
42 |    	for(i=0;i<n;i++){
43 |    		if(max(intervals[i].start,newInterval.start)<=min(intervals[i].end,newInterval.end)){
44 |    			if(p<0)
45 |    				p=i;
46 |    			q=i;
47 |    		}
48 |    	}
49 |    	if(p<0){
50 |    		vector<Interval> ::iterator it=intervals.begin();
51 |    		for(i=0;i<n;i++){
52 |    			if(newInterval.start < intervals[i].start){
53 |    				intervals.insert(it,newInterval);
54 |    				return intervals;
55 |    			}
56 |    			++it;
57 |    		}
58 |    		intervals.push_back(newInterval);
59 |    		return intervals;
60 |    	}	
61 |     intervals[p].start=min(intervals[p].start,newInterval.start);
62 |     intervals[p].end=max(intervals[q].end,newInterval.end);
63 |     for(i=1;i<n-q;i++){
64 |     	intervals[p+i].start=intervals[q+i].start;
65 |     	intervals[p+i].end=intervals[q+i].end;
66 | 
67 |     }
68 |     for(i=n-q+p;i<n;i++)
69 |     	intervals.pop_back();
70 |     return intervals;
71 | }
72 | 


--------------------------------------------------------------------------------
/C++/mergeTwoLists.cpp:
--------------------------------------------------------------------------------
 1 | class Solution {
 2 | public:
 3 |   ListNode *mergeTwoLists(ListNode *l1, ListNode *l2) {
 4 |     if(l1 == NULL) return l2;
 5 |     if(l2 == NULL) return l1;
 6 | 
 7 |     ListNode* head = NULL;    // head of the list to return
 8 | 
 9 |     // find first element (can use dummy node to put this part inside of the loop)
10 |     if(l1->val < l2->val) { 
11 |       head = l1; 
12 |       l1 = l1->next; 
13 |     } else { 
14 |       head = l2; 
15 |       l2 = l2->next; 
16 |     }
17 | 
18 |     ListNode* p = head;     // pointer to form new list
19 | 
20 |     while(l1 && l2){
21 |       if(l1->val < l2->val) { 
22 |         p->next = l1; 
23 |         l1 = l1->next; 
24 |       } else { 
25 |         p->next = l2; 
26 |         l2 = l2->next; 
27 |       }
28 |       p = p->next;
29 |     }
30 | 
31 |     // add the rest of the tail, done!
32 |     if (l1) { 
33 |       p->next=l1;
34 |     } else {
35 |       p->next=l2;
36 |     }
37 | 
38 |     return head;
39 |   }
40 | };
41 | 


--------------------------------------------------------------------------------
/C++/minStack.cpp:
--------------------------------------------------------------------------------
 1 | class MinStack {
 2 | private:
 3 |   stack<int> elementStack;
 4 |   stack<int> minimumStack;
 5 |   int minElement = -1;
 6 | public:
 7 |   void push(int x) {
 8 |     elementStack.push(x);
 9 |     if(elementStack.size() == 1 || x <= minElement) {
10 |       minimumStack.push(x);
11 |       minElement = x;
12 |     } 
13 |   }
14 | 
15 |   void pop() {
16 |     if (elementStack.top() == minElement) {
17 |       minimumStack.pop();
18 |       if (!minimumStack.empty()) {
19 |         minElement = minimumStack.top();
20 |       } else {
21 |         minElement = -1;
22 |       }
23 |     }
24 |     elementStack.pop();
25 |   }
26 | 
27 |   int top() {
28 |     if (elementStack.empty()) return -1;
29 |     return elementStack.top();
30 |   }
31 | 
32 |   int getMin() {
33 |     return minElement;
34 |   }
35 | };
36 | 


--------------------------------------------------------------------------------
/C++/numSetBits.cpp:
--------------------------------------------------------------------------------
 1 | int Solution::numSetBits(unsigned int A) {
 2 |   // Do not write main() function.
 3 |   // Do not read input, instead use the arguments to the function.
 4 |   // Do not print the output, instead return values as specified
 5 |   // Still have a doubt. Checkout www.interviewbit.com/pages/sample_codes/ for more details
 6 |   unsigned int count = 0;
 7 |   while(A){
 8 |     count += A & 1;
 9 |     A >>= 1;
10 |   }
11 |   return count;
12 | }
13 | 


--------------------------------------------------------------------------------
/C++/partition.cpp:
--------------------------------------------------------------------------------
 1 | class Solution {
 2 |     public:
 3 |         ListNode *partition(ListNode *head, int x) {
 4 | 
 5 |             if (!head) return NULL;
 6 |             ListNode * iterator = head;
 7 | 
 8 |             ListNode * start = new ListNode(0); // list of nodes greater than x
 9 |             ListNode * tail = start;
10 | 
11 |             ListNode * newHead = new ListNode(0);
12 |             newHead -> next = head;
13 |             ListNode * pre = newHead; // previous node, we need it for removing
14 | 
15 | 
16 |             while (iterator) {
17 |                 if (iterator -> val >= x) {
18 |                     pre -> next = iterator -> next; // remove from our list
19 |                     tail -> next = iterator; // add to list of nodes greater than x
20 |                     tail = tail -> next;
21 |                     iterator = iterator -> next;
22 |                     tail -> next = NULL;
23 |                 }
24 |                 else
25 |                     pre = iterator, iterator = iterator -> next;
26 |             }
27 |             pre -> next = start -> next;
28 |             return newHead -> next;
29 |         }
30 | };
31 | 


--------------------------------------------------------------------------------
/C++/pow.cpp:
--------------------------------------------------------------------------------
 1 | int pow(int x, int n, int p) {
 2 | 
 3 |   //handle base case
 4 |   if (n == 0) return 1 % p;
 5 | 
 6 |   long long ans = 1, base = x;
 7 | 
 8 |   while (n > 0) {
 9 |     // We need (base ** n) % p. 
10 |     // Now there are 2 cases. 
11 |     // 1) n is even. Then we can make base = base^2 and n = n / 2.
12 |     // 2) n is odd. So we need base * base^(n-1) 
13 |     if (n % 2 == 1) {
14 |       ans = (ans * base) % p;
15 |       n--;
16 |     } else {
17 |       base = (base * base) % p;
18 |       n /= 2;
19 |     }
20 |   }
21 |   if (ans < 0) ans = (ans + p) % p;
22 |   return ans;
23 | }
24 | 
25 | 


--------------------------------------------------------------------------------
/C++/prevSmaller.cpp:
--------------------------------------------------------------------------------
 1 | vector<int> Solution::prevSmaller(vector<int> &A) {
 2 |     //create answer vector and resize it to input vector
 3 |     vector<int> ans;
 4 |     ans.resize(A.size());
 5 | 
 6 |     //init stack
 7 |     stack<int> st;
 8 |     
 9 |     //start iterating through stack
10 |     for (int i = 0; i < A.size(); i++) {
11 |         //pop off the first element of the stack
12 |         while (!st.empty() && st.top() >= A[i]) 
13 |             st.pop();
14 |         //first value answer vector will always be -1
15 |         if (st.empty()) 
16 |             ans[i] = -1;
17 |         else 
18 |             ans[i] = st.top(); //set the value of a[i] to the lowest current stack value
19 |         
20 |         //keep pushing elements onto the stack
21 |         st.push(A[i]);
22 |     }
23 |     return ans;
24 | }
25 | 


--------------------------------------------------------------------------------
/C++/primeSum.cpp:
--------------------------------------------------------------------------------
 1 | class Solution {
 2 |     public:
 3 |     vector<int> primesum(int N) {
 4 |         
 5 |         // Generate isPrime List less equal than N
 6 |         vector<bool> isPrime(N + 1, true);
 7 |         isPrime[0] = false;
 8 |         isPrime[1] = false;
 9 |         
10 |         // Sieve of Erastothenes
11 |         for(int i = 2; i <= N; i++) {
12 |             if (!isPrime[i]) continue;
13 |             if (i > N / i) break;
14 |             for (int j = i * i; j <= N; j += i) isPrime[j] = false;
15 |         }
16 |         
17 |         for(int i = 2; i <= N; ++i) {
18 |             if(isPrime[i] && isPrime[N - i]) {
19 |                 vector<int> ans;
20 |                 ans.push_back(i);
21 |                 ans.push_back(N - i);
22 |                 return ans;
23 |             }
24 |         } 
25 |         
26 |         vector<int> ans; 
27 |         return ans;
28 |     }
29 | };
30 | 


--------------------------------------------------------------------------------
/C++/removeNthFromEnd.cpp:
--------------------------------------------------------------------------------
 1 | class Solution {
 2 | public:
 3 |   ListNode* removeNthFromEnd(ListNode* head, int n) {
 4 |     ListNode** t1 = &head, *t2 = head;
 5 |     for(int i = 1; i < n; ++i) {
 6 |       t2 = t2->next;
 7 |     }
 8 |     while(t2->next != NULL) {
 9 |       t1 = &((*t1)->next);
10 |       t2 = t2->next;
11 |     }
12 |     *t1 = (*t1)->next;
13 |     return head;
14 |   }
15 | };
16 | 


--------------------------------------------------------------------------------
/C++/reorderList.cpp:
--------------------------------------------------------------------------------
 1 | class Solution {
 2 | public:
 3 |     ListNode *mergeTwoLists(ListNode *l1, ListNode *l2) {
 4 |         if(l1 == NULL) return l2;
 5 |         if(l2 == NULL) return l1;
 6 | 
 7 |         ListNode* head = l1;    // head of the list to return
 8 |         l1 = l1->next;
 9 | 
10 |         ListNode* p = head;     // pointer to form new list
11 |         // A boolean to track which list we need to extract from. 
12 |         // We alternate between first and second list. 
13 |         bool curListNum = true;
14 | 
15 |         while(l1 && l2){
16 |             if(curListNum == false) {
17 |                 p->next = l1;
18 |                 l1 = l1->next;
19 |             } else {
20 |                 p->next = l2;
21 |                 l2 = l2->next;
22 |             }
23 |             p = p->next;
24 |             curListNum = !curListNum;
25 |         }
26 | 
27 |         // add the rest of the tail, done!
28 |         if (l1) {
29 |             p->next = l1;
30 |         } else {
31 |             p->next = l2;
32 |         }
33 | 
34 |         return head;
35 |     }
36 | 
37 |     ListNode *reverseLinkedList(ListNode *head) {
38 |         if (head->next == NULL) return head;
39 |         ListNode *cur = head, *nextNode = head->next, *tmp;
40 | 
41 |         while (nextNode != NULL) {
42 |             tmp = nextNode->next;
43 |             nextNode->next = cur;
44 |             cur = nextNode;
45 |             nextNode = tmp;
46 |         }
47 | 
48 |         head->next = nextNode;
49 |         return cur;
50 |     }
51 | 
52 |     ListNode* reorderList(ListNode *head) {
53 |         if(head == NULL || head->next == NULL || head->next->next==NULL)
54 |             return head;
55 | 
56 |         //find the middle of the list, and split into two lists.    
57 |         ListNode *slow = head,*fast = head;
58 |         while(slow != NULL && fast != NULL && fast->next != NULL && fast->next->next != NULL){
59 |             slow = slow->next;
60 |             fast = fast->next->next;
61 |         }
62 | 
63 |         ListNode *mid = slow->next;
64 |         slow->next = NULL;
65 | 
66 |         //reverse from the middle to the end
67 |         ListNode* secondHalfReversed = reverseLinkedList(mid);
68 | 
69 |         //merge these two list
70 |         return head = mergeTwoLists(head, secondHalfReversed);
71 |     }
72 | };
73 | 


--------------------------------------------------------------------------------
/C++/repeatedNum.cpp:
--------------------------------------------------------------------------------
 1 | int Solution::repeatedNumber(const vector<int> &A) {
 2 |   // Do not write main() function.
 3 |   // Do not read input, instead use the arguments to the function.
 4 |   // Do not print the output, instead return values as specified
 5 |   // Still have a doubt. Checkout www.interviewbit.com/pages/sample_codes/ for more details
 6 |   int slow = A[0];
 7 |   int fast = A[A[0]];
 8 |   while (slow != fast) {
 9 |     slow = A[slow];
10 |     fast = A[A[fast]];
11 |   }
12 | 
13 |   fast = 0;
14 |   while (slow != fast) {
15 |     slow = A[slow];
16 |     fast = A[fast];
17 |   }
18 |   return slow;
19 | }
20 | 


--------------------------------------------------------------------------------
/C++/reverse.cpp:
--------------------------------------------------------------------------------
 1 | class Solution {
 2 | public:
 3 |   int reverse(int x) {
 4 |     // solution without using strings
 5 |     int rev = 0, sign = 1, digit;
 6 |     if (x < 0) {
 7 |       sign = -1;
 8 |       x *= -1;
 9 |     }
10 |     while (x > 0) {
11 |       digit = x%10;
12 |       // check for overflow here 
13 |       if (rev > (INT_MAX / 10) || (rev == (INT_MAX / 10) && digit > (INT_MAX % 10))) {
14 |         return 0;
15 |       }
16 |       rev = rev * 10 + digit;
17 |       x/=10;
18 |     }
19 |     rev *= sign;        
20 |     return rev;
21 |   }
22 | };
23 | 


--------------------------------------------------------------------------------
/C++/reverseBetween.cpp:
--------------------------------------------------------------------------------
 1 | class Solution {
 2 | public:
 3 |  
 4 |     // Reverses the linkedList which starts from head, and extends to size nodes. 
 5 |     // Returns the end node. 
 6 |     // Also sets the head->next as endNode->next. 
 7 |     ListNode *reverseLinkedList(ListNode *head, int size) {
 8 |     if (size <= 1) return head; 
 9 |         ListNode *cur = head, *nextNode = head->next, *tmp;
10 | 
11 |     for (int i = 0; i < (size - 1); i++) {
12 |         tmp = nextNode->next;
13 |         nextNode->next = cur; 
14 |         cur = nextNode;
15 |         nextNode = tmp; 
16 |     }
17 | 
18 |     head->next = nextNode;
19 |     return cur;
20 |     }
21 | 
22 |     ListNode *reverseBetween(ListNode *head, int m, int n) {
23 |     // Introduce dummyhead to not handle corner cases. 
24 |     ListNode* dummyHead = new ListNode(0); 
25 |     dummyHead->next = head; 
26 | 
27 |     // Figure out the start node of the sublist we are going to reverse
28 |       ListNode* prev = dummyHead;
29 |     ListNode* cur = head; 
30 |     int index = 1;
31 |     while (index < m) {
32 |         prev = cur;
33 |         cur = cur->next;
34 |         index++;
35 |     }
36 | 
37 |     // At this point, we have start of sublist in cur, prev of startSubList in prev.
38 |     // Lets reverse the sublist now. 
39 |     ListNode* endSubList = reverseLinkedList(cur, n - m + 1);
40 |     prev->next = endSubList; 
41 | 
42 |     return dummyHead->next;
43 |     }
44 | };
45 | 


--------------------------------------------------------------------------------
/C++/roman2int.cpp:
--------------------------------------------------------------------------------
 1 | class Solution {
 2 | public:
 3 |   int romanToInt(string s) {
 4 |     int num = 0;
 5 |     int size = s.size();
 6 | 
 7 |     for (int i = 0; i < size; i++) {
 8 |       // Does lesser value precede higher value ? 
 9 |       if (i < (size - 1) && romanCharToInt(s[i]) < romanCharToInt(s[i + 1])) {
10 |         num -= romanCharToInt(s[i]);
11 |       } else {
12 |         num += romanCharToInt(s[i]);
13 |       }
14 |     }
15 |     return num;
16 |   }
17 | 
18 |   int romanCharToInt(char c) {
19 |     switch (c) {
20 |     case 'I':   return 1;
21 |     case 'V':   return 5;
22 |     case 'X':   return 10;
23 |     case 'L':   return 50;
24 |     case 'C':   return 100;
25 |     case 'D':   return 500;
26 |     case 'M':   return 1000;
27 |     default:    return 0;
28 |     }
29 |   }
30 | };
31 | 


--------------------------------------------------------------------------------
/C++/rotate.cpp:
--------------------------------------------------------------------------------
 1 | void Solution::rotate(vector<vector<int> > &matrix) {
 2 | 
 3 |         int len = matrix.size();
 4 |         for (int i = 0; i < len / 2; i++) {
 5 |             for (int j = i; j < len - i - 1; j++) {
 6 |             int tmp = matrix[i][j];
 7 |             matrix[i][j] = matrix[len - j - 1][i];
 8 |             matrix[len - j - 1][i] = matrix[len - i - 1][len - j - 1];
 9 |             matrix[len - i - 1][len - j - 1] = matrix[j][len - i - 1];
10 |             matrix[j][len - i - 1] = tmp;
11 |             }
12 |         }
13 |     }
14 | 


--------------------------------------------------------------------------------
/C++/rotateRight.cpp:
--------------------------------------------------------------------------------
 1 | class Solution {
 2 | public:
 3 |   ListNode *rotateRight(ListNode *head, int k) {
 4 |     if (head == NULL || head->next == NULL) return head;
 5 | 
 6 |     ListNode* dummy = new ListNode(0);
 7 |     dummy->next = head;
 8 | 
 9 |     ListNode *fast = dummy, *slow = dummy;
10 | 
11 |     int sizeOfList = 0; 
12 |     while (fast->next != NULL) {
13 |       fast = fast->next;
14 |       sizeOfList++;
15 |     }
16 | 
17 |     int firstNodePos = sizeOfList - (k % sizeOfList);
18 |     for (int i = 0; i < firstNodePos; i++) {
19 |       slow = slow->next;
20 |     }
21 | 
22 |     fast->next = dummy->next;
23 |     dummy->next = slow->next; 
24 |     slow->next = NULL;
25 | 
26 |     return dummy->next;
27 |   }
28 | };
29 | 


--------------------------------------------------------------------------------
/C++/rotatedsearch.cpp:
--------------------------------------------------------------------------------
 1 | class Solution {
 2 |     public:
 3 |         // returns the index.
 4 |         int findMin(const vector<int> &A, int start, int end) {
 5 |             if (start > end) return -1;
 6 |             if (start == end) {
 7 |                 return start;
 8 |             }
 9 |             int mid = (start + end) / 2;
10 |             if (A[mid] < A[end]) {
11 |                 return findMin(A, start, mid);
12 |             } else if (A[mid] > A[end]) {
13 |                 return findMin(A, mid + 1, end);
14 |             } else {
15 |                 // should not come here 
16 |                 int index1 = findMin(A,start, mid);
17 |                 int index2 = findMin(A, mid + 1, end);
18 |                 if (index1 != -1 && index2 != -1) {
19 |                     if (A[index1] < A[index2]) return index1;
20 |                     return index2;
21 |                 } else if (index1 != -1) return index1;
22 |                 else return index2;
23 |             }
24 |         }
25 | 
26 |         int binarySearch(const vector<int> &A, int start, int end, int target) {
27 |             if (start > end) return -1; 
28 |             if (start == end) {
29 |                 if (A[start] == target)
30 |                     return start;
31 |                 return -1;
32 |             }
33 |             int mid = (start + end) / 2;
34 |             if (A[mid] < target) {
35 |                 return binarySearch(A, mid + 1, end, target);
36 |             } else return binarySearch(A, start, mid, target);
37 |         }
38 | 
39 |         int search(const vector<int> &A, int target) {
40 |             int n = A.size();
41 |             int index = findMin(A, 0, n - 1);
42 |             int index1 = binarySearch(A, 0, index, target); 
43 |             if (index1 != -1) return index1;
44 |             return binarySearch(A, index, n - 1, target);
45 |         }
46 | };
47 | 


--------------------------------------------------------------------------------
/C++/searchInsert.cpp:
--------------------------------------------------------------------------------
 1 | int Solution::searchInsert(vector<int> &A, int B) {
 2 |   // Do not write main() function.
 3 |   // Do not read input, instead use the arguments to the function.
 4 |   // Do not print the output, instead return values as specified
 5 |   // Still have a doubt. Checkout www.interviewbit.com/pages/sample_codes/ for more details
 6 |   if(A.empty() || B <= A[0])
 7 |     return 0;
 8 |     
 9 |   int low = 0, hi = A.size() - 1;
10 |     
11 |   while(low <= hi){
12 |     int mid = low + (hi - low) / 2;
13 |         
14 |     if(B == A[mid])
15 |       return mid;    
16 |     else if (B > A[mid])
17 |       low = mid + 1;
18 |     else 
19 |       hi = mid - 1;
20 |   }
21 |   return low;
22 | }
23 | 


--------------------------------------------------------------------------------
/C++/searchMatrix.cpp:
--------------------------------------------------------------------------------
 1 | bool searchMatrix(vector<vector<int> > &matrix, int target) {
 2 |             int n = matrix.size();
 3 |             int m = matrix[0].size();
 4 |             int l = 0, r = m * n - 1;
 5 |             while (l != r){
 6 |                 int mid = (l + r - 1) >> 1;
 7 |                 if (matrix[mid / m][mid % m] < target)
 8 |                     l = mid + 1;
 9 |                 else 
10 |                     r = mid;
11 |             }
12 |             return matrix[r / m][r % m] == target;
13 |         }
14 | 


--------------------------------------------------------------------------------
/C++/setMatrixZeros.cpp:
--------------------------------------------------------------------------------
 1 | void Solution::setZeroes(vector<vector<int> > &matrix) {
 2 |         // Start typing your C/C++ solution below
 3 |         // DO NOT write int main() function
 4 |         int row = matrix.size();
 5 |         if (row==0){return;}
 6 |         int col = matrix[0].size();
 7 |         if (col==0){return;}
 8 |          
 9 |         bool fc0=false;
10 |         bool fr0=false;
11 |          
12 |         for (int i=0;i<col;i++){
13 |             if (matrix[0][i]==0){fr0 = true;}
14 |         }
15 |          
16 |         for (int i=0;i<row;i++){
17 |             if (matrix[i][0]==0){fc0 = true;}
18 |         }
19 |          
20 |         for (int i=1;i<row;i++){
21 |             for (int j=1;j<col;j++){
22 |                 if (matrix[i][j]==0){
23 |                     matrix[i][0]=0;
24 |                     matrix[0][j]=0;
25 |                 }
26 |             }
27 |         }
28 |          
29 |          
30 |         for (int i=1;i<col;i++){
31 |             if (matrix[0][i]==0){
32 |                 for(int j=0;j<row;j++){
33 |                     matrix[j][i]=0;
34 |                 }
35 |             }
36 |         }
37 |          
38 |         for (int i=1;i<row;i++){
39 |             if (matrix[i][0]==0){
40 |                 for(int j=0;j<col;j++){
41 |                     matrix[i][j]=0;
42 |                 }
43 |             }
44 |         }
45 |          
46 |         if (fr0){
47 |             for (int i=0;i<col;i++){matrix[0][i]=0;}
48 |         }
49 |         if (fc0){
50 |             for (int i=0;i<row;i++){matrix[i][0]=0;}
51 |         }
52 |          
53 |         return;
54 |          
55 |     }
56 | 


--------------------------------------------------------------------------------
/C++/singleNumberi.cpp:
--------------------------------------------------------------------------------
1 | int Solution::singleNumber(const vector<int> &A) {
2 |   // Do not write main() function.
3 |   // Do not read input, instead use the arguments to the function.
4 |   // Do not print the output, instead return values as specified
5 |   // Still have a doubt. Checkout www.interviewbit.com/pages/sample_codes/ for more details
6 |   return accumulate(A.cbegin(), A.cend(),
7 |                     0, std::bit_xor<int>());
8 | }
9 | 


--------------------------------------------------------------------------------
/C++/singleNumberii.cpp:
--------------------------------------------------------------------------------
 1 | class Solution {
 2 | public:
 3 |   int singleNumber(const vector<int> &A) {
 4 |     int result = 0;
 5 |     for (int i = 0; i < A.size(); i++) {
 6 |       result ^= A[i];
 7 |     }
 8 |     return result;
 9 |   }
10 | };
11 | 


--------------------------------------------------------------------------------
/C++/sqrt.cpp:
--------------------------------------------------------------------------------
 1 | int Solution::sqrt(int A) {
 2 |     //base cases
 3 |     if(A == 0 || A == 1)
 4 |         return A;
 5 |     
 6 |     //algo
 7 |     long long start = 1, end = A, ans;
 8 |     while(start <= end){
 9 |         long long mid = (start + end) >> 1;
10 |         
11 |         //case 1: if perfect square
12 |         if(mid * mid == A)
13 |             return (int)mid;
14 |         //case 2: increment right
15 |         if(mid * mid < A){
16 |             start = mid + 1;
17 |             ans = mid;
18 |         }
19 |         //case 3: increment left
20 |         else 
21 |             end = mid - 1;
22 |     }
23 |     return (int)ans;
24 | }
25 | 
26 | 


--------------------------------------------------------------------------------
/C++/substr.cpp:
--------------------------------------------------------------------------------
 1 | int Solution::strStr(const string &haystack, const string &needle) {
 2 |   // Do not write main() function.
 3 |   // Do not read input, instead use the arguments to the function.
 4 |   // Do not print the output, instead return values as specified
 5 |   if (needle.empty()) {
 6 |     return 0;
 7 |   }
 8 | 
 9 |   for (int i = 0; i + needle.length() < haystack.length() + 1; ++i) {
10 |     if (haystack.substr(i, needle.length()) == needle) {
11 |       return i;
12 |     }
13 |   }
14 |   return -1;
15 | }
16 | 


--------------------------------------------------------------------------------
/C++/swapColor.cpp:
--------------------------------------------------------------------------------
 1 | class Solution {
 2 | public:
 3 |   void sortColors(int A[], int n)  {     
 4 |     int n = A.size(); 
 5 |     int k = n - 1;
 6 |     int i = 0;
 7 |     for (; i < n; ++i)
 8 |       {
 9 |         if (A[i] != 0)
10 |           {
11 |             break;
12 |           }
13 |       }
14 | 
15 |     int j = i;
16 |     for (; i <= k; ++i)
17 |       {
18 |         if (A[i] == 0)
19 |           {
20 |             swap(A[j++], A[i]);
21 |           }
22 |         else if (A[i] == 2)
23 |           {
24 |             swap(A[i--], A[k--]);
25 |           }
26 |       }
27 |   }
28 | };
29 | 


--------------------------------------------------------------------------------
/C++/titleToNumber.cpp:
--------------------------------------------------------------------------------
 1 | class Solution {
 2 | public:
 3 |     int titleToNumber(string s) {
 4 |        int result = 0;
 5 |        for (int i = 0; i < s.size(); i++) {
 6 |                result = result * 26 + (s[i] - 'A' + 1);
 7 |        }
 8 |        return result;
 9 |     }
10 | };
11 | 


--------------------------------------------------------------------------------
/C++/trailingZeros.cpp:
--------------------------------------------------------------------------------
 1 | class Solution {
 2 | public:
 3 |     int trailingZeroes(int n) {
 4 |         int sum = 0;
 5 |         while (n / 5 > 0) {
 6 |             sum += (n / 5);
 7 |             n /= 5;
 8 |         }
 9 |         return sum;
10 |     }
11 | };
12 | 


--------------------------------------------------------------------------------
/C++/uniquePaths.cpp:
--------------------------------------------------------------------------------
 1 | class Solution {
 2 |     public:
 3 |         int uniquePaths(int m, int n) {
 4 |             // m+n-2 C n-1 = (m+n-2)! / (n-1)! (m-1)! 
 5 |             long long ans = 1;
 6 |             for (int i = n; i < (m + n - 1); i++) {
 7 |                 ans *= i;
 8 |                 ans /= (i - n + 1);
 9 |             }
10 |             return (int)ans;
11 |         }
12 | };
13 | 


--------------------------------------------------------------------------------
/C++/wave.cpp:
--------------------------------------------------------------------------------
 1 | void swap(int& a,int &b){
 2 | 	int c=a;
 3 | 	a=b;
 4 | 	b=c;
 5 | }
 6 | 
 7 | vector<int> Solution::wave(vector<int> &A) {
 8 |   // Do not write main() function.
 9 |   // Do not read input, instead use the arguments to the function.
10 |   // Do not print the output, instead return values as specified
11 |   // Still have a doubt. Checkout www.interviewbit.com/pages/sample_codes/ for more details
12 |   int n = A.size();
13 |     
14 |   sort(A.begin(), A.begin()+n);
15 |   for(int i = 0; i < n-1; i += 2){
16 |     swap(A[i],A[i+1]);
17 |   }
18 |   return A;
19 | }
20 | 


--------------------------------------------------------------------------------
/LICENSE:
--------------------------------------------------------------------------------
  1 |                     GNU GENERAL PUBLIC LICENSE
  2 |                        Version 3, 29 June 2007
  3 | 
  4 |  Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
  5 |  Everyone is permitted to copy and distribute verbatim copies
  6 |  of this license document, but changing it is not allowed.
  7 | 
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198 | receive it, in any medium, provided that you conspicuously and
199 | appropriately publish on each copy an appropriate copyright notice;
200 | keep intact all notices stating that this License and any
201 | non-permissive terms added in accord with section 7 apply to the code;
202 | keep intact all notices of the absence of any warranty; and give all
203 | recipients a copy of this License along with the Program.
204 | 
205 |   You may charge any price or no price for each copy that you convey,
206 | and you may offer support or warranty protection for a fee.
207 | 
208 |   5. Conveying Modified Source Versions.
209 | 
210 |   You may convey a work based on the Program, or the modifications to
211 | produce it from the Program, in the form of source code under the
212 | terms of section 4, provided that you also meet all of these conditions:
213 | 
214 |     a) The work must carry prominent notices stating that you modified
215 |     it, and giving a relevant date.
216 | 
217 |     b) The work must carry prominent notices stating that it is
218 |     released under this License and any conditions added under section
219 |     7.  This requirement modifies the requirement in section 4 to
220 |     "keep intact all notices".
221 | 
222 |     c) You must license the entire work, as a whole, under this
223 |     License to anyone who comes into possession of a copy.  This
224 |     License will therefore apply, along with any applicable section 7
225 |     additional terms, to the whole of the work, and all its parts,
226 |     regardless of how they are packaged.  This License gives no
227 |     permission to license the work in any other way, but it does not
228 |     invalidate such permission if you have separately received it.
229 | 
230 |     d) If the work has interactive user interfaces, each must display
231 |     Appropriate Legal Notices; however, if the Program has interactive
232 |     interfaces that do not display Appropriate Legal Notices, your
233 |     work need not make them do so.
234 | 
235 |   A compilation of a covered work with other separate and independent
236 | works, which are not by their nature extensions of the covered work,
237 | and which are not combined with it such as to form a larger program,
238 | in or on a volume of a storage or distribution medium, is called an
239 | "aggregate" if the compilation and its resulting copyright are not
240 | used to limit the access or legal rights of the compilation's users
241 | beyond what the individual works permit.  Inclusion of a covered work
242 | in an aggregate does not cause this License to apply to the other
243 | parts of the aggregate.
244 | 
245 |   6. Conveying Non-Source Forms.
246 | 
247 |   You may convey a covered work in object code form under the terms
248 | of sections 4 and 5, provided that you also convey the
249 | machine-readable Corresponding Source under the terms of this License,
250 | in one of these ways:
251 | 
252 |     a) Convey the object code in, or embodied in, a physical product
253 |     (including a physical distribution medium), accompanied by the
254 |     Corresponding Source fixed on a durable physical medium
255 |     customarily used for software interchange.
256 | 
257 |     b) Convey the object code in, or embodied in, a physical product
258 |     (including a physical distribution medium), accompanied by a
259 |     written offer, valid for at least three years and valid for as
260 |     long as you offer spare parts or customer support for that product
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262 |     copy of the Corresponding Source for all the software in the
263 |     product that is covered by this License, on a durable physical
264 |     medium customarily used for software interchange, for a price no
265 |     more than your reasonable cost of physically performing this
266 |     conveying of source, or (2) access to copy the
267 |     Corresponding Source from a network server at no charge.
268 | 
269 |     c) Convey individual copies of the object code with a copy of the
270 |     written offer to provide the Corresponding Source.  This
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272 |     only if you received the object code with such an offer, in accord
273 |     with subsection 6b.
274 | 
275 |     d) Convey the object code by offering access from a designated
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277 |     Corresponding Source in the same way through the same place at no
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280 |     copy the object code is a network server, the Corresponding Source
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286 |     available for as long as needed to satisfy these requirements.
287 | 
288 |     e) Convey the object code using peer-to-peer transmission, provided
289 |     you inform other peers where the object code and Corresponding
290 |     Source of the work are being offered to the general public at no
291 |     charge under subsection 6d.
292 | 
293 |   A separable portion of the object code, whose source code is excluded
294 | from the Corresponding Source as a System Library, need not be
295 | included in conveying the object code work.
296 | 
297 |   A "User Product" is either (1) a "consumer product", which means any
298 | tangible personal property which is normally used for personal, family,
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300 | into a dwelling.  In determining whether a product is a consumer product,
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302 | product received by a particular user, "normally used" refers to a
303 | typical or common use of that class of product, regardless of the status
304 | of the particular user or of the way in which the particular user
305 | actually uses, or expects or is expected to use, the product.  A product
306 | is a consumer product regardless of whether the product has substantial
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308 | the only significant mode of use of the product.
309 | 
310 |   "Installation Information" for a User Product means any methods,
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313 | a modified version of its Corresponding Source.  The information must
314 | suffice to ensure that the continued functioning of the modified object
315 | code is in no case prevented or interfered with solely because
316 | modification has been made.
317 | 
318 |   If you convey an object code work under this section in, or with, or
319 | specifically for use in, a User Product, and the conveying occurs as
320 | part of a transaction in which the right of possession and use of the
321 | User Product is transferred to the recipient in perpetuity or for a
322 | fixed term (regardless of how the transaction is characterized), the
323 | Corresponding Source conveyed under this section must be accompanied
324 | by the Installation Information.  But this requirement does not apply
325 | if neither you nor any third party retains the ability to install
326 | modified object code on the User Product (for example, the work has
327 | been installed in ROM).
328 | 
329 |   The requirement to provide Installation Information does not include a
330 | requirement to continue to provide support service, warranty, or updates
331 | for a work that has been modified or installed by the recipient, or for
332 | the User Product in which it has been modified or installed.  Access to a
333 | network may be denied when the modification itself materially and
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335 | protocols for communication across the network.
336 | 
337 |   Corresponding Source conveyed, and Installation Information provided,
338 | in accord with this section must be in a format that is publicly
339 | documented (and with an implementation available to the public in
340 | source code form), and must require no special password or key for
341 | unpacking, reading or copying.
342 | 
343 |   7. Additional Terms.
344 | 
345 |   "Additional permissions" are terms that supplement the terms of this
346 | License by making exceptions from one or more of its conditions.
347 | Additional permissions that are applicable to the entire Program shall
348 | be treated as though they were included in this License, to the extent
349 | that they are valid under applicable law.  If additional permissions
350 | apply only to part of the Program, that part may be used separately
351 | under those permissions, but the entire Program remains governed by
352 | this License without regard to the additional permissions.
353 | 
354 |   When you convey a copy of a covered work, you may at your option
355 | remove any additional permissions from that copy, or from any part of
356 | it.  (Additional permissions may be written to require their own
357 | removal in certain cases when you modify the work.)  You may place
358 | additional permissions on material, added by you to a covered work,
359 | for which you have or can give appropriate copyright permission.
360 | 
361 |   Notwithstanding any other provision of this License, for material you
362 | add to a covered work, you may (if authorized by the copyright holders of
363 | that material) supplement the terms of this License with terms:
364 | 
365 |     a) Disclaiming warranty or limiting liability differently from the
366 |     terms of sections 15 and 16 of this License; or
367 | 
368 |     b) Requiring preservation of specified reasonable legal notices or
369 |     author attributions in that material or in the Appropriate Legal
370 |     Notices displayed by works containing it; or
371 | 
372 |     c) Prohibiting misrepresentation of the origin of that material, or
373 |     requiring that modified versions of such material be marked in
374 |     reasonable ways as different from the original version; or
375 | 
376 |     d) Limiting the use for publicity purposes of names of licensors or
377 |     authors of the material; or
378 | 
379 |     e) Declining to grant rights under trademark law for use of some
380 |     trade names, trademarks, or service marks; or
381 | 
382 |     f) Requiring indemnification of licensors and authors of that
383 |     material by anyone who conveys the material (or modified versions of
384 |     it) with contractual assumptions of liability to the recipient, for
385 |     any liability that these contractual assumptions directly impose on
386 |     those licensors and authors.
387 | 
388 |   All other non-permissive additional terms are considered "further
389 | restrictions" within the meaning of section 10.  If the Program as you
390 | received it, or any part of it, contains a notice stating that it is
391 | governed by this License along with a term that is a further
392 | restriction, you may remove that term.  If a license document contains
393 | a further restriction but permits relicensing or conveying under this
394 | License, you may add to a covered work material governed by the terms
395 | of that license document, provided that the further restriction does
396 | not survive such relicensing or conveying.
397 | 
398 |   If you add terms to a covered work in accord with this section, you
399 | must place, in the relevant source files, a statement of the
400 | additional terms that apply to those files, or a notice indicating
401 | where to find the applicable terms.
402 | 
403 |   Additional terms, permissive or non-permissive, may be stated in the
404 | form of a separately written license, or stated as exceptions;
405 | the above requirements apply either way.
406 | 
407 |   8. Termination.
408 | 
409 |   You may not propagate or modify a covered work except as expressly
410 | provided under this License.  Any attempt otherwise to propagate or
411 | modify it is void, and will automatically terminate your rights under
412 | this License (including any patent licenses granted under the third
413 | paragraph of section 11).
414 | 
415 |   However, if you cease all violation of this License, then your
416 | license from a particular copyright holder is reinstated (a)
417 | provisionally, unless and until the copyright holder explicitly and
418 | finally terminates your license, and (b) permanently, if the copyright
419 | holder fails to notify you of the violation by some reasonable means
420 | prior to 60 days after the cessation.
421 | 
422 |   Moreover, your license from a particular copyright holder is
423 | reinstated permanently if the copyright holder notifies you of the
424 | violation by some reasonable means, this is the first time you have
425 | received notice of violation of this License (for any work) from that
426 | copyright holder, and you cure the violation prior to 30 days after
427 | your receipt of the notice.
428 | 
429 |   Termination of your rights under this section does not terminate the
430 | licenses of parties who have received copies or rights from you under
431 | this License.  If your rights have been terminated and not permanently
432 | reinstated, you do not qualify to receive new licenses for the same
433 | material under section 10.
434 | 
435 |   9. Acceptance Not Required for Having Copies.
436 | 
437 |   You are not required to accept this License in order to receive or
438 | run a copy of the Program.  Ancillary propagation of a covered work
439 | occurring solely as a consequence of using peer-to-peer transmission
440 | to receive a copy likewise does not require acceptance.  However,
441 | nothing other than this License grants you permission to propagate or
442 | modify any covered work.  These actions infringe copyright if you do
443 | not accept this License.  Therefore, by modifying or propagating a
444 | covered work, you indicate your acceptance of this License to do so.
445 | 
446 |   10. Automatic Licensing of Downstream Recipients.
447 | 
448 |   Each time you convey a covered work, the recipient automatically
449 | receives a license from the original licensors, to run, modify and
450 | propagate that work, subject to this License.  You are not responsible
451 | for enforcing compliance by third parties with this License.
452 | 
453 |   An "entity transaction" is a transaction transferring control of an
454 | organization, or substantially all assets of one, or subdividing an
455 | organization, or merging organizations.  If propagation of a covered
456 | work results from an entity transaction, each party to that
457 | transaction who receives a copy of the work also receives whatever
458 | licenses to the work the party's predecessor in interest had or could
459 | give under the previous paragraph, plus a right to possession of the
460 | Corresponding Source of the work from the predecessor in interest, if
461 | the predecessor has it or can get it with reasonable efforts.
462 | 
463 |   You may not impose any further restrictions on the exercise of the
464 | rights granted or affirmed under this License.  For example, you may
465 | not impose a license fee, royalty, or other charge for exercise of
466 | rights granted under this License, and you may not initiate litigation
467 | (including a cross-claim or counterclaim in a lawsuit) alleging that
468 | any patent claim is infringed by making, using, selling, offering for
469 | sale, or importing the Program or any portion of it.
470 | 
471 |   11. Patents.
472 | 
473 |   A "contributor" is a copyright holder who authorizes use under this
474 | License of the Program or a work on which the Program is based.  The
475 | work thus licensed is called the contributor's "contributor version".
476 | 
477 |   A contributor's "essential patent claims" are all patent claims
478 | owned or controlled by the contributor, whether already acquired or
479 | hereafter acquired, that would be infringed by some manner, permitted
480 | by this License, of making, using, or selling its contributor version,
481 | but do not include claims that would be infringed only as a
482 | consequence of further modification of the contributor version.  For
483 | purposes of this definition, "control" includes the right to grant
484 | patent sublicenses in a manner consistent with the requirements of
485 | this License.
486 | 
487 |   Each contributor grants you a non-exclusive, worldwide, royalty-free
488 | patent license under the contributor's essential patent claims, to
489 | make, use, sell, offer for sale, import and otherwise run, modify and
490 | propagate the contents of its contributor version.
491 | 
492 |   In the following three paragraphs, a "patent license" is any express
493 | agreement or commitment, however denominated, not to enforce a patent
494 | (such as an express permission to practice a patent or covenant not to
495 | sue for patent infringement).  To "grant" such a patent license to a
496 | party means to make such an agreement or commitment not to enforce a
497 | patent against the party.
498 | 
499 |   If you convey a covered work, knowingly relying on a patent license,
500 | and the Corresponding Source of the work is not available for anyone
501 | to copy, free of charge and under the terms of this License, through a
502 | publicly available network server or other readily accessible means,
503 | then you must either (1) cause the Corresponding Source to be so
504 | available, or (2) arrange to deprive yourself of the benefit of the
505 | patent license for this particular work, or (3) arrange, in a manner
506 | consistent with the requirements of this License, to extend the patent
507 | license to downstream recipients.  "Knowingly relying" means you have
508 | actual knowledge that, but for the patent license, your conveying the
509 | covered work in a country, or your recipient's use of the covered work
510 | in a country, would infringe one or more identifiable patents in that
511 | country that you have reason to believe are valid.
512 | 
513 |   If, pursuant to or in connection with a single transaction or
514 | arrangement, you convey, or propagate by procuring conveyance of, a
515 | covered work, and grant a patent license to some of the parties
516 | receiving the covered work authorizing them to use, propagate, modify
517 | or convey a specific copy of the covered work, then the patent license
518 | you grant is automatically extended to all recipients of the covered
519 | work and works based on it.
520 | 
521 |   A patent license is "discriminatory" if it does not include within
522 | the scope of its coverage, prohibits the exercise of, or is
523 | conditioned on the non-exercise of one or more of the rights that are
524 | specifically granted under this License.  You may not convey a covered
525 | work if you are a party to an arrangement with a third party that is
526 | in the business of distributing software, under which you make payment
527 | to the third party based on the extent of your activity of conveying
528 | the work, and under which the third party grants, to any of the
529 | parties who would receive the covered work from you, a discriminatory
530 | patent license (a) in connection with copies of the covered work
531 | conveyed by you (or copies made from those copies), or (b) primarily
532 | for and in connection with specific products or compilations that
533 | contain the covered work, unless you entered into that arrangement,
534 | or that patent license was granted, prior to 28 March 2007.
535 | 
536 |   Nothing in this License shall be construed as excluding or limiting
537 | any implied license or other defenses to infringement that may
538 | otherwise be available to you under applicable patent law.
539 | 
540 |   12. No Surrender of Others' Freedom.
541 | 
542 |   If conditions are imposed on you (whether by court order, agreement or
543 | otherwise) that contradict the conditions of this License, they do not
544 | excuse you from the conditions of this License.  If you cannot convey a
545 | covered work so as to satisfy simultaneously your obligations under this
546 | License and any other pertinent obligations, then as a consequence you may
547 | not convey it at all.  For example, if you agree to terms that obligate you
548 | to collect a royalty for further conveying from those to whom you convey
549 | the Program, the only way you could satisfy both those terms and this
550 | License would be to refrain entirely from conveying the Program.
551 | 
552 |   13. Use with the GNU Affero General Public License.
553 | 
554 |   Notwithstanding any other provision of this License, you have
555 | permission to link or combine any covered work with a work licensed
556 | under version 3 of the GNU Affero General Public License into a single
557 | combined work, and to convey the resulting work.  The terms of this
558 | License will continue to apply to the part which is the covered work,
559 | but the special requirements of the GNU Affero General Public License,
560 | section 13, concerning interaction through a network will apply to the
561 | combination as such.
562 | 
563 |   14. Revised Versions of this License.
564 | 
565 |   The Free Software Foundation may publish revised and/or new versions of
566 | the GNU General Public License from time to time.  Such new versions will
567 | be similar in spirit to the present version, but may differ in detail to
568 | address new problems or concerns.
569 | 
570 |   Each version is given a distinguishing version number.  If the
571 | Program specifies that a certain numbered version of the GNU General
572 | Public License "or any later version" applies to it, you have the
573 | option of following the terms and conditions either of that numbered
574 | version or of any later version published by the Free Software
575 | Foundation.  If the Program does not specify a version number of the
576 | GNU General Public License, you may choose any version ever published
577 | by the Free Software Foundation.
578 | 
579 |   If the Program specifies that a proxy can decide which future
580 | versions of the GNU General Public License can be used, that proxy's
581 | public statement of acceptance of a version permanently authorizes you
582 | to choose that version for the Program.
583 | 
584 |   Later license versions may give you additional or different
585 | permissions.  However, no additional obligations are imposed on any
586 | author or copyright holder as a result of your choosing to follow a
587 | later version.
588 | 
589 |   15. Disclaimer of Warranty.
590 | 
591 |   THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
592 | APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
593 | HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
594 | OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
595 | THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
596 | PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
597 | IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
598 | ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
599 | 
600 |   16. Limitation of Liability.
601 | 
602 |   IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
603 | WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
604 | THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
605 | GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
606 | USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
607 | DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
608 | PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
609 | EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
610 | SUCH DAMAGES.
611 | 
612 |   17. Interpretation of Sections 15 and 16.
613 | 
614 |   If the disclaimer of warranty and limitation of liability provided
615 | above cannot be given local legal effect according to their terms,
616 | reviewing courts shall apply local law that most closely approximates
617 | an absolute waiver of all civil liability in connection with the
618 | Program, unless a warranty or assumption of liability accompanies a
619 | copy of the Program in return for a fee.
620 | 
621 |                      END OF TERMS AND CONDITIONS
622 | 
623 |             How to Apply These Terms to Your New Programs
624 | 
625 |   If you develop a new program, and you want it to be of the greatest
626 | possible use to the public, the best way to achieve this is to make it
627 | free software which everyone can redistribute and change under these terms.
628 | 
629 |   To do so, attach the following notices to the program.  It is safest
630 | to attach them to the start of each source file to most effectively
631 | state the exclusion of warranty; and each file should have at least
632 | the "copyright" line and a pointer to where the full notice is found.
633 | 
634 |     {one line to give the program's name and a brief idea of what it does.}
635 |     Copyright (C) {year}  {name of author}
636 | 
637 |     This program is free software: you can redistribute it and/or modify
638 |     it under the terms of the GNU General Public License as published by
639 |     the Free Software Foundation, either version 3 of the License, or
640 |     (at your option) any later version.
641 | 
642 |     This program is distributed in the hope that it will be useful,
643 |     but WITHOUT ANY WARRANTY; without even the implied warranty of
644 |     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
645 |     GNU General Public License for more details.
646 | 
647 |     You should have received a copy of the GNU General Public License
648 |     along with this program.  If not, see <http://www.gnu.org/licenses/>.
649 | 
650 | Also add information on how to contact you by electronic and paper mail.
651 | 
652 |   If the program does terminal interaction, make it output a short
653 | notice like this when it starts in an interactive mode:
654 | 
655 |     {project}  Copyright (C) {year}  {fullname}
656 |     This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
657 |     This is free software, and you are welcome to redistribute it
658 |     under certain conditions; type `show c' for details.
659 | 
660 | The hypothetical commands `show w' and `show c' should show the appropriate
661 | parts of the General Public License.  Of course, your program's commands
662 | might be different; for a GUI interface, you would use an "about box".
663 | 
664 |   You should also get your employer (if you work as a programmer) or school,
665 | if any, to sign a "copyright disclaimer" for the program, if necessary.
666 | For more information on this, and how to apply and follow the GNU GPL, see
667 | <http://www.gnu.org/licenses/>.
668 | 
669 |   The GNU General Public License does not permit incorporating your program
670 | into proprietary programs.  If your program is a subroutine library, you
671 | may consider it more useful to permit linking proprietary applications with
672 | the library.  If this is what you want to do, use the GNU Lesser General
673 | Public License instead of this License.  But first, please read
674 | <http://www.gnu.org/philosophy/why-not-lgpl.html>.
675 | 


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/Python/__init__.py:
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https://raw.githubusercontent.com/Alex-Keyes/InterviewBit/d0a02b1170c1391d07a8962e8ae1935e2d79ebb2/Python/__init__.py


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/Python/addTwoNumbers.py:
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 1 | # Definition for singly-linked list.
 2 | # class ListNode:
 3 | #     def __init__(self, x):
 4 | #         self.val = x
 5 | #         self.next = None
 6 | 
 7 | class Solution:
 8 |     # @param A : head node of linked list
 9 |     # @param B : head node of linked list
10 |     # @return the head node in the linked list
11 |     def addTwoNumbers(self, A, B):
12 |         a, b = A, B
13 |         head = ListNode(0)
14 |         cur_sum = head
15 |         while a != None or b != None or cur_sum.val > 9:
16 |             carry = cur_sum.val / 10
17 |             cur_sum.val %= 10
18 |             a_val = 0 if a == None else a.val
19 |             b_val = 0 if b == None else b.val
20 |             next_val = a_val + b_val + carry
21 |             cur_sum.next = ListNode(next_val)
22 |             cur_sum = cur_sum.next
23 |             a = None if a == None else a.next
24 |             b = None if b == None else b.next
25 |         return head.next
26 | 


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/Python/addone.py:
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 1 | class Solution:
 2 |     # @param A : list of integers
 3 |     # @return a list of integers
 4 |     def plusOne(self, A):
 5 |         while (A[0] == 0) and len(A) > 1:
 6 |             del (A[0])
 7 |         if A[0] == 0 and len(A) == 1:
 8 |             A[0] = 1
 9 |             return A
10 |         i = len(A) - 1
11 |         carry = 1
12 |         while True:
13 |             value = A[i] + carry
14 |             if value >= 10:
15 |                 A[i] = value % 10
16 |                 carry = value // 10
17 |             else:
18 |                 A[i] = value
19 |                 break
20 |             if i == 0:
21 |                 A.insert(0, carry)
22 |                 break
23 |             i -= 1
24 |         return A
25 | 


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/Python/arrange.py:
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 1 | class Solution:
 2 |     # @param A : list of integers
 3 |     def arrange(self, A):
 4 |         n = len(A)
 5 |         B = [0]*n
 6 |         for i in range(n):
 7 |             B[i] = A[i]
 8 |         for i in range(n):
 9 |             A[i] = B[B[i]]
10 |         
11 | 


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/Python/convertToTitle.py:
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 1 | class Solution:
 2 |     # @param A : integer
 3 |     # @return a strings
 4 |     def convertToTitle(self, A):
 5 |         ret = ''
 6 |         while A != 0:
 7 |             A = A-1
 8 |             temp = A%26
 9 |             A /= 26
10 |             ret += chr(temp+ord('A'))
11 |         return ret[::-1]
12 | 


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/Python/detectCycle.py:
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 1 | class Solution:
 2 |     # @param A : head node of linked list
 3 |     # @return the head node in the linked list
 4 |     def detectCycle(self, A):
 5 |         seen = set()
 6 |         while A:
 7 |             if A.val in seen:
 8 |                 return A
 9 |             else:
10 |                 seen.add(A.val)
11 |                 A = A.next
12 | 


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/Python/flip.py:
--------------------------------------------------------------------------------
 1 | class Solution:
 2 |     # @param A : string
 3 |     # @return a list of integers
 4 |     def flip(self, A):
 5 |         max_diff = 0
 6 |         diff = 0
 7 |         ones = 0
 8 |         start = 0
 9 |         ans = None
10 | 
11 |         for i, a in enumerate(A):
12 |             diff += (1 if a is '0' else -1)
13 | 
14 |             if diff < 0:
15 |                 diff = 0
16 |                 start = i + 1
17 |                 continue
18 | 
19 |             if diff > max_diff:
20 |                 max_diff = diff
21 |                 ans = [start, i]
22 | 
23 |         if ans is None:
24 |             return []
25 |         return map(lambda x: x + 1, ans)
26 | 


--------------------------------------------------------------------------------
/Python/gcd.py:
--------------------------------------------------------------------------------
 1 | class Solution:
 2 |     # @param A : integer
 3 |     # @param B : integer
 4 |     # @return an integer
 5 |     def gcd(self, a, b):
 6 |         if (b == 0):
 7 | 		    return a
 8 |         else:
 9 | 		    return self.gcd(b, a%b)
10 | 


--------------------------------------------------------------------------------
/Python/generateMatrix.py:
--------------------------------------------------------------------------------
 1 | class Solution:
 2 |     # @param A : integer
 3 |     # @return a list of list of integers
 4 |     def generateMatrix(self, A):
 5 |         n = A
 6 |         ret = [[0]*n]
 7 |         for i in range(n-1):
 8 | 	        ret.append([0]*n)
 9 | 
10 |         T = 0
11 |         B = n-1
12 |         L = 0
13 |         R = n-1
14 |         direction = 0
15 |         num = 1
16 |         while T <=B and L <=R:
17 |         	if direction == 0:
18 |         		for i in range(L,R+1):
19 |         			ret[T][i] = num
20 |         			num += 1
21 |                     T += 1
22 |         		    direction = 1
23 |         	elif direction == 1:
24 |         		for i in range(T,B+1):
25 |         			ret[i][R] = num
26 |         			num += 1
27 |         		    R -= 1
28 |         		    direction = 2
29 |         	elif direction == 2:
30 |         		for i in range(R,L-1,-1):
31 |         			ret[B][i] = num
32 |         			num += 1
33 |         		    B -= 1
34 |         		    direction = 3
35 |         	else:
36 |         		for i in range(B,T-1,-1):
37 |         			ret[i][L] = num
38 |         			num += 1
39 |         		    L += 1
40 |         		    direction = 0
41 |         return ret
42 | 


--------------------------------------------------------------------------------
/Python/generatePascal.py:
--------------------------------------------------------------------------------
 1 | class Solution:
 2 |     # @param A : integer
 3 |     # @return a list of list of integers
 4 |     def generate(self, numRows):
 5 |         result = []
 6 |         for i in xrange(numRows):
 7 |             result.append([])
 8 |             for j in xrange(i + 1):
 9 |                 if j in (0, i):
10 |                     result[i].append(1)
11 |                 else:
12 |                     result[i].append(result[i - 1][j - 1] + result[i - 1][j])
13 |         return result
14 | 


--------------------------------------------------------------------------------
/Python/getRow.py:
--------------------------------------------------------------------------------
 1 | class Solution:
 2 |     # @param A : integer
 3 |     # @return a list of integers
 4 |     def getRow(self, A):
 5 |         A += 1
 6 |         ret = []
 7 |         if A == 0:
 8 |             return ret
 9 |         ret = [[1]]
10 |         for i in range(2,A+1):
11 |             ret.append([0]*i)
12 |             ret[i-1][0] = 1
13 |             ret[i-1][-1] = 1
14 |             for j in range(1,i-1):
15 |                 ret[i-1][j] = ret[i-2][j-1]+ret[i-2][j]
16 |         return ret[-1]
17 | 


--------------------------------------------------------------------------------
/Python/isPalindrome.py:
--------------------------------------------------------------------------------
 1 | class Solution:
 2 |     # @param A : integer
 3 |     # @return an integer
 4 |     def isPalindrome(self, A):
 5 |         A = str(A)
 6 |         for i in range(len(A)/2+1):
 7 |             if A[i] != A[-(i+1)]:
 8 |                 return 0
 9 |         return 1
10 | 


--------------------------------------------------------------------------------
/Python/isPower.py:
--------------------------------------------------------------------------------
 1 | class Solution:
 2 |     # @param A : integer
 3 |     # @return a boolean
 4 |     def isPower(self, N):
 5 |         if N == 0:
 6 |             return False
 7 |         if N == 1:
 8 |             return True
 9 |         for p in xrange(2,33):
10 |             for A in xrange(2, int(N**(1.0 / p)) + 2):
11 |                 if A**p == N:
12 |                     return True
13 |         return False
14 | 


--------------------------------------------------------------------------------
/Python/maxSet.py:
--------------------------------------------------------------------------------
 1 | class Solution:
 2 |     # @param A : list of integers
 3 |     # @return a list of integers
 4 |     def maxset(self, A):
 5 |         max_ending_here = 0
 6 |         start_ending_here = 0
 7 |         end_ending_here = 0
 8 |         max_so_far = 0
 9 |         start_so_far = 0
10 |         end_so_far = 0
11 |         
12 |         allNegative = True
13 |         n = len(A)
14 |         if n == 0:
15 |             return []
16 |         for i in range(n):
17 |             if A[i] >= 0:
18 |                 allNegative = False
19 |             if max_ending_here + A[i] >= max_ending_here:
20 |                 max_ending_here += A[i]
21 |                 end_ending_here = i
22 |             else:
23 |                 if max_so_far < max_ending_here:
24 |                     max_so_far = max_ending_here
25 |                     start_so_far = start_ending_here
26 |                     end_so_far = end_ending_here
27 |                 elif max_so_far <= max_ending_here:
28 |                     if end_ending_here - start_ending_here > end_so_far - start_so_far:
29 |                         max_so_far = max_ending_here
30 |                         start_so_far = start_ending_here
31 |                         end_so_far = end_ending_here
32 |                 max_ending_here = 0
33 |                 start_ending_here = i+1
34 |                 end_ending_here = 0
35 |         
36 |         if max_so_far < max_ending_here:
37 |             max_so_far = max_ending_here
38 |             start_so_far = start_ending_here
39 |             end_so_far = end_ending_here
40 |         elif max_so_far <= max_ending_here:
41 |             if end_ending_here - start_ending_here > end_so_far - start_so_far:
42 |                 max_so_far = max_ending_here
43 |                 start_so_far = start_ending_here
44 |                 end_so_far = end_ending_here
45 |         if allNegative:
46 |             return []
47 |         else:
48 |             return A[start_so_far:end_so_far+1]
49 | 


--------------------------------------------------------------------------------
/Python/nextPermutation.py:
--------------------------------------------------------------------------------
 1 | class Solution:
 2 |     # @param A : list of integers
 3 |     # @return the same list of integer after modification
 4 |     def nextPermutation(self, A):
 5 |         if len(A) == 1:
 6 |             return A
 7 | 
 8 |         if len(A) == 2:
 9 |             self.swap(A, 0, 1)
10 |             return A
11 | 
12 |         for i in xrange(len(A) - 2, 0, -1):
13 | 
14 |             if A[i - 1] >= A[i] >= A[i + 1] and i != 1:
15 |                 continue
16 | 
17 |             if A[i - 1] >= A[i] >= A[i + 1] and i == 1:
18 |                 for j in xrange(len(A) / 2):
19 |                     self.swap(A, j, len(A) - 1 - j)
20 |                 return A
21 | 
22 |             if (A[i - 1] >= A[i] or A[i - 1] <= A[i]) and A[i] <= A[i + 1]:
23 |                 self.swap(A, i, i + 1)
24 |                 return A
25 | 
26 |             if A[i] >= A[i - 1] and A[i] >= A[i + 1] and A[i - 1] >= A[i + 1]:
27 |                 temp = sorted(A[i:])
28 |                 for j in xrange(i, len(A)):
29 |                     A[j] = temp[j - j]
30 |                     temp.pop(j - j)
31 |                 low = A[i - 1]
32 |                 for j in xrange(i, len(A)):
33 |                     if A[j] > low:
34 |                         self.swap(A, j, i - 1)
35 |                         break
36 |                 return A
37 | 
38 |             if A[i] >= A[i - 1] and A[i] >= A[i + 1] and A[i - 1] <= A[i + 1]:
39 |                 temp = sorted(A[i:])
40 |                 for j in xrange(i, len(A)):
41 |                     A[j] = temp[j - j]
42 |                     temp.pop(j - j)
43 |                 low = A[i - 1]
44 |                 for j in xrange(i, len(A)):
45 |                     if A[j] > low:
46 |                         self.swap(A, j, i - 1)
47 |                         break
48 |                 return A
49 | 
50 |     def swap(self, A, index_i, index_j):
51 |         temp = A[index_i]
52 |         A[index_i] = A[index_j]
53 |         A[index_j] = temp
54 | 
55 | 
56 | 


--------------------------------------------------------------------------------
/Python/partition.py:
--------------------------------------------------------------------------------
 1 | class Solution:
 2 |     # @param {ListNode} head
 3 |     # @param {integer} x
 4 |     # @return {ListNode}
 5 |     def partition(self, head, x):
 6 |         if not head:
 7 |             return None
 8 | 
 9 |         less, greaterEqual = ListNode(0), ListNode(0)
10 |         tempLess, tempGreaterEqual, temp = less, greaterEqual, head
11 |         while temp:
12 |             if temp.val < x:
13 |                 tempLess.next = temp
14 |                 tempLess = tempLess.next
15 |             else:
16 |                 tempGreaterEqual.next = temp
17 |                 tempGreaterEqual = tempGreaterEqual.next
18 | 
19 |             cur = temp
20 |             temp = temp.next
21 |             cur.next = None
22 | 
23 |         tempLess.next = greaterEqual.next
24 |         return less.next
25 | 


--------------------------------------------------------------------------------
/Python/primeSum.py:
--------------------------------------------------------------------------------
 1 | class Solution:
 2 |     def primesum(self, n):
 3 |         for i in xrange(2, n):
 4 |             if self.is_prime(i) and self.is_prime(n - i):
 5 |                 return i, n - i
 6 | 
 7 |     def is_prime(self, n):
 8 |         if n < 2:
 9 |             return False
10 | 
11 |         for i in xrange(2, int(n**0.5) + 1):
12 |             if n % i == 0:
13 |                 return False
14 | 
15 |         return True
16 | 


--------------------------------------------------------------------------------
/Python/reorderList.py:
--------------------------------------------------------------------------------
 1 | # Definition for singly-linked list.
 2 | # class ListNode:
 3 | #     def __init__(self, x):
 4 | #         self.val = x
 5 | #         self.next = None
 6 | 
 7 | class Solution:
 8 |     # @param A : head node of linked list
 9 |     # @return the head node in the linked list
10 |     def reorderList(self, A):
11 |         arr = []
12 |         ca = A
13 |         alen = 0
14 |         while ca:
15 |             arr.append(ca)
16 |             alen += 1
17 |             ca = ca.next
18 |         cn = arr[0]
19 |         for i in xrange(1, alen):
20 |             if i%2 == 0:
21 |                 cn.next = arr[i/2]
22 |                 cn = cn.next
23 |                 if i == alen - 1:
24 |                     cn.next = None
25 |             else:
26 |                 cn.next = arr[alen - i/2 - 1]
27 |                 cn = cn.next
28 |                 if i == alen - 1:
29 |                     cn.next = None
30 |         return A
31 | 


--------------------------------------------------------------------------------
/Python/reverse.py:
--------------------------------------------------------------------------------
 1 | class Solution:
 2 |     # @param A : integer
 3 |     # @return an integer
 4 |     def reverse(self, A):
 5 |         A = str(A)
 6 |         if A[0] == '-':
 7 |             A = '-'+A[1:][::-1]
 8 |         else:
 9 |             A = A[::-1]
10 |             A = int(A)
11 |         if A > 2**31 or A < -2**31:
12 |             return 0
13 |         return A
14 | 


--------------------------------------------------------------------------------
/Python/titleToNumber.py:
--------------------------------------------------------------------------------
 1 | class Solution:
 2 |     # @param A : string
 3 |     # @return an integer
 4 |     def titleToNumber(self, A):
 5 |         n = len(A)
 6 |         A = A[::-1]
 7 |         ret = 0
 8 |         for i in range(n):
 9 |             ret += (26**(i))*(ord(A[i])-ord('A')+1)
10 |         return ret
11 | 


--------------------------------------------------------------------------------
/Python/trailingZeros.py:
--------------------------------------------------------------------------------
 1 | class Solution:
 2 |     # @param A : integer
 3 |     # @return an integer
 4 |     def trailingZeroes(self, n):
 5 |         i = 1
 6 |         result = 0
 7 |         while n >= i:
 8 |             i *= 5
 9 |             result += n/i  # (taking floor, just like Python or Java does)
10 |         return result
11 | 


--------------------------------------------------------------------------------
/Python/uniquePaths.py:
--------------------------------------------------------------------------------
1 | class Solution:
2 |     # @param A : integer
3 |     # @param B : integer
4 |     # @return an integer
5 |     def uniquePaths(self, A, B):
6 |         return math.factorial(A+B-2)/(math.factorial(A-1)*math.factorial(B-1))
7 | 


--------------------------------------------------------------------------------
/README.md:
--------------------------------------------------------------------------------
 1 | <p align="center">
 2 | <img src="img/ib-logo-square.png" alt="ib-logo-square.png">
 3 | </p>
 4 | 
 5 | # InterviewBit Solutions
 6 | 
 7 | ![languages-Python%20&%20C++-orange.svg](https://img.shields.io/badge/languages-Python%20&%20C++-orange.svg) [![License-GNU-red.svg](https://img.shields.io/badge/License-GNU-red.svg)](https://img.shields.io/badge/License-GNU-red.svg) [![codebeat-A-brightgreen.svg](https://img.shields.io/badge/codebeat-A-brightgreen.svg)](https://codebeat.co/projects/github-com-alex-keyes-interviewbit) 
 8 | 
 9 | This is a repository of solutions to all problems I've solved on InterviewBit. I am not quite sure exactly how many problems there are on the website, but I'll be updating this with every problem I solve. Please issue a pull request if you think you have a better solution or something I could improve upon.
10 | 
11 | # Topics
12 | 
13 | *   [Time Complexity](https://github.com/Alex-Keyes/InterviewBit#Time+Complexity)
14 | *   [Arrays](https://github.com/Alex-Keyes/InterviewBit#Arrays)
15 | *   [Math](https://github.com/Alex-Keyes/InterviewBit#Math)
16 | *   [Binary Search](https://github.com/Alex-Keyes/InterviewBit#Binary+Search)
17 | *   [Linked Lists](https://github.com/Alex-Keyes/InterviewBit#Linked+Lists)
18 | *   [Stack and Queue](https://github.com/Alex-Keyes/InterviewBit#Stack+and+Queue)
19 | 
20 | # Problem Lists
21 | ## [Time Complexity](https://www.interviewbit.com/courses/programming/topics/time-complexity/)
22 | [Answers](https://github.com/Alex-Keyes/InterviewBit/blob/master/timeComplexity.md)
23 | 
24 |  <!--  my birthday, where we are going skiing - vail and what's happening this weekend -->
25 | 
26 | ## [Arrays](https://www.interviewbit.com/courses/programming/topics/arrays)
27 | | SubTopic | Title | Solution | Notes |
28 | | ---      | ---   | ---      | ---   |
29 | | Simulation Array          | [Pascal Triangle Rows](https://www.interviewbit.com/problems/pascal-triangle-rows/) | [cpp](./C++/generatePascal.cpp) [python](./Python/generatePascal.py) |
30 | | Array math                | [Min Steps in Infinite Grid](https://www.interviewbit.com/problems/min-steps-in-infinite-grid/)           | [C++](/C++/coverPoints.cpp)                                        | Simpler Than I originally thought. |
31 | | Array math                | [Max Sum Contiguous Subarray](https://www.interviewbit.com/problems/max-sum-contiguous-subarray/)         | [C++](/C++/maxSubArray.cpp)                                        |                                    |
32 | | Array math                | [Add One To Number](https://www.interviewbit.com/problems/add-one-to-number/)                             | [Python](/Python/addone.py)                                        |                                    |
33 | | Array math                | [Repeat and Missing Number Array](https://www.interviewbit.com/problems/repeat-and-missing-number-array/) | [Python](/Python/repeatedNumber.py)                                |                                    |
34 | | Array math                | [Flip](https://www.interviewbit.com/problems/flip/)                                                       | [Python](/Python/flip.py)                                          |                                    |
35 | | Simulation array          | [Max Non Negative SubArray](https://www.interviewbit.com/problems/max-non-negative-subarray/)             | [C++](/C++/maxSet.cpp) [Python](file:Python/maxSet.py)             |                                    |
36 | | Simulation array          | [Kth Row of Pascal's Triangle](https://www.interviewbit.com/problems/kth-row-of-pascals-triangle/)        | [Python](/Python/getRow.py)                                        |                                    |
37 | | Simulation array          | [Pascal Triangle Rows](https://www.interviewbit.com/problems/pascal-triangle-rows/)                       | [Python](/Python/generatePascal.py)                                |                                    |
38 | | Simulation array          | [Spiral Order Matrix II](https://www.interviewbit.com/problems/spiral-order-matrix-ii/)                   | [C++](/C++/generateMatrix.cpp) [Python](/Python/generateMatrix.py) |                                    |
39 | | Simulation array          | [Anti Diagonals](https://www.interviewbit.com/problems/anti-diagonals/)                                   | [C++](/C++/diagonal.cpp)                                           |                                    |
40 | | Arrangement               | [Rotate Matrix](https://www.interviewbit.com/problems/rotate-matrix/)                                     | [C++](/C++/rotate.cpp)                                             |                                    |
41 | | Arrangement               | [Largest Number](https://www.interviewbit.com/problems/largest-number/)                                   | [C++](C++/largestNum.cpp)                                          |                                    |
42 | | Arrangement               | [Next Permutation](https://www.interviewbit.com/problems/next-permutation/)                               | [Python](/Python/nextPermutation.py)                               |                                    |
43 | | Bucketing or sorting      | Hotel Bookings Possible                                                                                   |                                                                    |                                    |
44 | | Bucketing or sorting      | [Wave Array](https://www.interviewbit.com/problems/wave-array/)                                           | [C++](/C++/wave.cpp)                                               |                                    |
45 | | Bucketing or sorting      | [Largest Number]([https://www.interviewbit.com/problems/largest-number/)                                  | [C++](/C++/largestNum.cpp)                                         |                                    |
46 | | Bucketing or sorting      | Max Distance                                                                                              |                                                                    |                                    |
47 | | Bucketing or sorting      | Maximum Consecutive Gap                                                                                   |                                                                    |                                    |
48 | | Bucketing or sorting      | [Find Duplicate in Array](https://www.interviewbit.com/problems/find-duplicate-in-array/)                 | [C++](/C++/repeatedNum.cpp)                                        |                                    |
49 | | Value ranges              | [Merge Intervals](https://www.interviewbit.com/problems/merge-intervals/)                                 | [C++](/C++/mergeIntervals.cpp)                                     |                                    |
50 | | Value ranges              | Merge Overlapping Intervals                                                                               |                                                                    |                                    |
51 | | Space recycle             | [Set Matrix Zeros](https://www.interviewbit.com/problems/set-matrix-zeros/)                               | [C++](/C++/setMatrixZeros.cpp)                                     |                                    |
52 | | Space recycle             | First Missing Integer                                                                                     |                                                                    |                                    |
53 | | Missing / repeated number | First Missing Integer                                                                                     |                                                                    |                                    |
54 | | Missing / repeated number | Repeat and Missing Number Array                                                                           |                                                                    |                                    |
55 | | Missing / repeated number | Find Duplicate in Array                                                                                   |                                                                    |                                    |
56 | | Missing / repeated number | N/3 Repeat Number                                                                                         |                                                                    |                                    |
57 | ## [Math](http://interviewbit.com/courses/programming/topics/math/)
58 | ## [Binary Search](https://www.interviewbit.com/courses/programming/topics/binary-search/)
59 | ## [Stack and Queue](https://www.interviewbit.com/courses/programming/topics/stacks-and-queues/)
60 | ## [Linked Lists](https://www.interviewbit.com/courses/programming/topics/linked-lists/)
61 | 


--------------------------------------------------------------------------------
/README.org:
--------------------------------------------------------------------------------
  1 | [[file:img/ib-logo-square.png]]
  2 | * InterviewBit Solutions
  3 | 
  4 | [[https://img.shields.io/badge/languages-Python & C++-orange.svg]] [[https://img.shields.io/badge/License-GNU-red.svg][https://img.shields.io/badge/License-GNU-red.svg]] [[https://codebeat.co/projects/github-com-alex-keyes-interviewbit][https://img.shields.io/badge/codebeat-A-brightgreen.svg]] [[https://github.com/syl20bnr/spacemacs][file:https://cdn.rawgit.com/syl20bnr/spacemacs/442d025779da2f62fc86c2082703697714db6514/assets/spacemacs-badge.svg]]
  5 | 
  6 | This is a repository of solutions to all problems I've solved on InterviewBit.
  7 | I am not quite sure exactly how many problems there are on the website, but I'll be updating this with every problem I solve.
  8 | Please issue a pull request if you think you have a better solution or something I could improve upon.
  9 | 
 10 | * Topics
 11 |  - [[Arrays][Arrays]]
 12 |  - [[Math][Math]]
 13 |  - [[Binary Search][Binary Search]]
 14 |  - [[String][String]]
 15 |  - [[Bit Manipulation][Bit Manipulationpri]]
 16 |  - [[Two-Pointers][Two-Pointers]]
 17 |  - [[Linked Lists][Linked Lists]]
 18 |  - [[Stack and Queue][Stack and Queue]]
 19 | 
 20 | * Problem Lists
 21 | ** [[https://www.interviewbit.com/courses/programming/topics/arrays][Arrays]]
 22 |  | SubTopic                  | Title                           | Solution   | Notes                              |
 23 |  | Array math                | [[https://www.interviewbit.com/problems/min-steps-in-infinite-grid/][Min Steps in Infinite Grid]]      | [[/C++/coverPoints.cpp][C++]]        | Simpler Than I originally thought. |
 24 |  | Array math                | [[https://www.interviewbit.com/problems/max-sum-contiguous-subarray/][Max Sum Contiguous Subarray]]     | [[/C++/maxSubArray.cpp][C++]]        |                                    |
 25 |  | Array math                | Add One To Number               |            |                                    |
 26 |  | Array math                | Repeat and Missing Number Array |            |                                    |
 27 |  | Array math                | Flip                            |            |                                    |
 28 |  | Simulation array          | [[https://www.interviewbit.com/problems/max-non-negative-subarray/][Max Non Negative SubArray]]       | [[/C++/maxSet.cpp][C++]] [[file:Python/maxSet.py][Python]]       |                                    |
 29 |  | Simulation array          | Kth Row of Pascal's Triangle    |            |                                    |
 30 |  | Simulation array          | [[https://www.interviewbit.com/problems/pascal-triangle-rows/][Pascal Triangle Rows]]            | [[/Python/generatePascal.py][Python]]     |                                    |
 31 |  | Simulation array          | [[https://www.interviewbit.com/problems/spiral-order-matrix-ii/][Spiral Order Matrix II]]          | [[/C++/generateMatrix.cpp][C++]] [[/Python/generateMatrix.py][Python]] |                                    |
 32 |  | Simulation array          | [[https://www.interviewbit.com/problems/anti-diagonals/][Anti Diagonals]]                  | [[/C++/diagonal.cpp][C++]]        |                                    |
 33 |  | Arrangement               | [[https://www.interviewbit.com/problems/rotate-matrix/][Rotate Matrix]]                   | [[/C++/rotate.cpp][C++]]        |                                    |
 34 |  | Arrangement               | [[https://www.interviewbit.com/problems/largest-number/][Largest Number]]                  | [[/C++/largestNum.cpp][C++]]        |                                    |
 35 |  | Arrangement               | Next Permutation                |            |                                    |
 36 |  | Bucketing or sorting      | Hotel Bookings Possible         |            |                                    |
 37 |  | Bucketing or sorting      | [[https://www.interviewbit.com/problems/wave-array/][Wave Array]]                      | [[/C++/wave.cpp][C++]]        |                                    |
 38 |  | Bucketing or sorting      | [[https://www.interviewbit.com/problems/largest-number/][Largest Number]]                  | [[/C++/largestNum.cpp][C++]]        |                                    |
 39 |  | Bucketing or sorting      | Max Distance                    |            |                                    |
 40 |  | Bucketing or sorting      | Maximum Consecutive Gap         |            |                                    |
 41 |  | Bucketing or sorting      | [[https://www.interviewbit.com/problems/find-duplicate-in-array/][Find Duplicate in Array]]         | [[/C++/repeatedNum.cpp][C++]]        |                                    |
 42 |  | Value ranges              | [[https://www.interviewbit.com/problems/merge-intervals/][Merge Intervals]]                 | [[/C++/mergeIntervals.cpp][C++]]        |                                    |
 43 |  | Value ranges              | Merge Overlapping Intervals     |            |                                    |
 44 |  | Space recycle             | [[https://www.interviewbit.com/problems/set-matrix-zeros/][Set Matrix Zeros]]                | [[/C++/setMatrixZeros.cpp][C++]]        |                                    |
 45 |  | Space recycle             | First Missing Integer           |            |                                    |
 46 |  | Missing / repeated number | First Missing Integer           |            |                                    |
 47 |  | Missing / repeated number | Repeat and Missing Number Array |            |                                    |
 48 |  | Missing / repeated number | Find Duplicate in Array         |            |                                    |
 49 |  | Missing / repeated number | N/3 Repeat Number               |            |                                    |
 50 | 
 51 | ** [[http://interviewbit.com/courses/programming/topics/math/][Math]]
 52 | | SubTopic        | Title                                | Solution   | Notes |
 53 | |                 |                                      |            |       |
 54 | |-----------------+--------------------------------------+------------+-------|
 55 | | Adhoc           | [[https://www.interviewbit.com/problems/prime-sum/][Prime Sum]]                            | [[file:Python/primeSum.py][Python]] [[file:C++/primeSum.cpp][C++]]          |       |
 56 | | Adhoc           | [[https://www.interviewbit.com/problems/power-of-two-integers/][Power of Two Integers]]                | [[file:C++/isPower.cpp][C++]] [[file:Python/isPower.py][Python]] |       |
 57 | | Base conversion | [[https://www.interviewbit.com/problems/excel-column-number/][Excel Column Number]]                  |  [[file:C++/titleToNumber.cpp][C++]] [[file:Python/titleToNumber.py][Python]]          |       |
 58 | | Base conversion | [[https://www.interviewbit.com/problems/excel-column-title/][Excel Column Title]]                   | [[file:C++/convertToTitle.cpp][C++]]  [[file:Python/convertToTitle.py][Python]]          |       |
 59 | | Digit op        | [[https://www.interviewbit.com/problems/palindrome-integer/][Palindrome Integer]]                  | [[file:C++/isPalindrome.cpp][C++]] [[file:Python/isPalindrome.py][Python]]          |       |
 60 | | Digit op        | [[https://www.interviewbit.com/problems/reverse-integer/][Reverse Integer]]                      | [[file:C++/reverse.cpp][C++]] [[file:Python/reverse.py][Python]] |       |
 61 | | Number theory   | [[https://www.interviewbit.com/problems/greatest-common-divisor/][Greatest Common Divisor]]              |  [[file:C++/gcd.cpp][C++]] [[file:Python/gcd.py][Python]]        |       |
 62 | | Number theory   | [[https://www.interviewbit.com/problems/trailing-zeros-in-factorial/][Trailing Zeros in Factorial]]          | [[file:C++/trailingZeros.cpp][C++]] [[file:Python/trailingZeros.py][Python]]     |       |
 63 | | Number theory   | Sorted Permutation Rank              |            |       |
 64 | | Number theory   | Sorted Permutation Rank with Repeats |            |       |
 65 | | Number encoding | [[https://www.interviewbit.com/problems/rearrange-array/][Rearrange Array]]                      | [[file:C++/arrange.cpp][C++]] [[file:Python/arrange.py][Python]]            |       |
 66 | | Combinatorics   | [[https://www.interviewbit.com/problems/grid-unique-paths/][Grid Unique Paths]]                    | [[file:C++/uniquePaths.cpp][C++]] [[file:Python/uniquePaths.py][Python]]           | Note the difference in length between the Python and C++ solutions       |
 67 | 
 68 | ** [[https://www.interviewbit.com/courses/programming/topics/binary-search/][Binary Search]]
 69 | 
 70 | | SubTopic               | Title                       | Solution | Notes |
 71 | |                        |                             |          |       |
 72 | |------------------------+-----------------------------+----------+-------|
 73 | | Simple binary search   | Matrix Search               |          |       |
 74 | | Simple binary search   | Search for a Range          |          |       |
 75 | | Simple binary search   | Sorted Insert Position      |          |       |
 76 | | Search answer          | Square Root of Integer      |          |       |
 77 | | Search answer          | Painter's Partition Problem |          |       |
 78 | | Search answer          | Allocate Books              |          |       |
 79 | | Search step simulation | Implement Power Function	   |          |       |
 80 | | Sort modification      | Rotated Sorted Array Search |          |       |
 81 | | Sort modification      | Median of Array             |          |       |
 82 | 
 83 | ** [[https://www.interviewbit.com/courses/programming/topics/stacks-and-queues/][Stack and Queue]]
 84 | | SubTopic       | Title                   | Solution | Notes                                                  |
 85 | | Multiple Stack | [[ https://www.interviewbit.com/problems/min-stack/][Min Stack]]               | [[/C++/minStack.cpp][C++]]      | IB has an annoying redefinition issue in their buffer. |
 86 | | Stack math     | [[https://www.interviewbit.com/problems/evaluate-expression/][Evaluate Expression]]     | [[/C++/evalRPN.cpp][C++]]      |                                                        |
 87 | | Stack Simple   | [[https://www.interviewbit.com/problems/redundant-braces/][Redundant Braces]]        | [[/C++/braces.cpp][C++]]      |                                                        |
 88 | | CleverStack    | [[https://www.interviewbit.com/problems/nearest-smaller-element/][Nearest Smaller Element]] | [[/C++/prevSmaller.cpp][C++]]      | Forgot to use a solution vector the first time around. |
 89 | |                |                         |          |                                                        |
 90 | 
 91 | ** [[https://www.interviewbit.com/courses/programming/topics/linked-lists/][Linked Lists]]
 92 | | Subtopic       | Title                                 | Solution   | Notes                           |
 93 | | Examples       | [[https://www.interviewbit.com/problems/intersection-of-linked-lists/][Intersection of Linked List]]           | [[/C++/getIntersectionNode.cpp][C++]]        |                                 |
 94 | | List 2 Pointer | [[https://www.interviewbit.com/problems/palindrome-list/][Palindrome List]]                       | [[file:C++/listPalindrome.cpp][C++]]        |                                 |
 95 | | List 2 Pointer | [[https://www.interviewbit.com/problems/merge-two-sorted-lists/][Merge Sorted List]]                     | [[file:C++/mergeTwoLists.cpp][C++]]        |                                 |
 96 | | List 2 Pointer | [[https://www.interviewbit.com/problems/remove-duplicates-from-sorted-list/][Remove Duplicates from sorted list i]]  | [[file:C++/deleteDuplicatesi.cpp][C++]]        |                                 |
 97 | | List 2 Pointer | [[https://www.interviewbit.com/problems/remove-duplicates-from-sorted-list-ii/][Remove Duplicates from sorted list ii]] | [[file:C++/deleteDuplicatesii.cpp][C++]]        |                                 |
 98 | | List 2 Pointer | [[https://www.interviewbit.com/problems/remove-nth-node-from-list-end/][Remove nth node from list end]]         | [[file:C++/removeNthFromEnd.cpp][C++]]        |                                 |
 99 | | List 2 Pointer | [[https://www.interviewbit.com/problems/rotate-list/][Rotate List]]                           | [[file:C++/rotateRight.cpp][C++]]        |                                 |
100 | | List 2 Pointer | [[https://www.interviewbit.com/problems/reverse-link-list-ii/][Reverse Linked List II]]                | [[file:C++/reverseBetween.cpp][C++]]        |                                 |
101 | | List 2 Pointer | [[https://www.interviewbit.com/problems/reorder-list/][Reorder List]]                          | [[file:C++/reorderList.cpp][C++]] [[file:Python/reorderList.py][Python]] |                                 |
102 | | List Math      | [[https://www.interviewbit.com/problems/add-two-numbers-as-lists/][Add Two Numbers as Lists]]              | [[file:C++/addTwoNumber.cpp][C++]] [[file:Python/addTwoNumbers.py][Python]] |                                 |
103 | | List Math      | [[https://www.interviewbit.com/problems/list-cycle/][List Cycle]]                            | [[file:C++/detectCycle.cpp][C++]] [[file:Python/detectCycle.py][Python]] | Python Solution is much simpler |
104 | | List Sort      | [[https://www.interviewbit.com/problems/partition-list/][Partiton List]]                         | [[file:C++/partition.cpp][C++]] [[file:Python/partition.py][Python]] |                                 |
105 | 


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/img/ib-logo-square.png:
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https://raw.githubusercontent.com/Alex-Keyes/InterviewBit/d0a02b1170c1391d07a8962e8ae1935e2d79ebb2/img/ib-logo-square.png


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/repeatedNumber.py:
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 1 | class Solution:
 2 |     # @param A : tuple of integers
 3 |     # @return a list of integers
 4 |     def repeatedNumber(self, A):
 5 |         a=list(A)
 6 |         a.sort()
 7 |         r=0
 8 |         m=0
 9 |         for i in range(0,len(a)-1):
10 |             if a[i]==a[i+1]:
11 |                 r=a[i]
12 |                 break
13 |         s=sum(a)
14 |         d=(len(a)*(len(a)+1))/2
15 |         m=r+(d-s)
16 |         return [r,m]
17 | 


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/timeComplexity.md:
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 1 | # Time Complexity
 2 | Since these questions are all multiple choice I'm going to write down the write answers here
 3 | 
 4 | ## Basic Primer
 5 | | Name | Answer |
 6 | | --- | --- |
 7 | | [LOOP_CMPL](https://www.interviewbit.com/problems/loop_cmpl) | O(N + M) time, O(1) space |
 8 | | [NESTED_CMPL](https://www.interviewbit.com/problems/nested_cmpl) | O(N * N) time, O(1) space |
 9 | | [NESTED_CMPL2](https://www.interviewbit.com/problems/nested_cmpl2/) | O(N*N) |
10 | | [CHOOSE4](https://www.interviewbit.com/problems/choose4/) | X will always be a better choice for large inputs
11 | 
12 | ## Math
13 | | Name | Answer |
14 | | --- | --- |
15 | | [WHILE_CMPL](https://www.interviewbit.com/problems/while_cmpl/) | O(log N)
16 | | [NESTED_CMPL3](https://www.interviewbit.com/problems/nested_cmpl3/) | O(N)
17 | 
18 | 
19 | ## Compare Functions
20 | | Name | Answer |
21 | | --- | --- |
22 | | [CHOOSE1](https://www.interviewbit.com/problems/choose1/) | n^3 / (sqrt(n))
23 | | [CHOOSE2](https://www.interviewbit.com/problems/choose2/) | f3, f2, f4, f1
24 | | [CHOOSE3](https://www.interviewbit.com/problems/choose3/) | c 
25 | 
26 | ## Function calling itself
27 | | Name | Answer |
28 | | --- | --- |
29 | |[REC_CMPL1](https://www.interviewbit.com/problems/rec_cmpl1/) | O(N)
30 | |[REC_CMPL2](https://www.interviewbit.com/problems/rec_cmpl2/) | O(2^(R + C))
31 | 
32 | # Amortized 
33 | | Name | Answer |
34 | | --- | --- |
35 | | [AMORTIZED1](https://www.interviewbit.com/problems/amortized1/) | O(N)
36 | 


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