├── README.md
├── Faulty Keyboard: Problem Statement
├── Faulty-Keyboard:Solution.cpp
├── College Applications: Problem Statement
└── CollegeApps-Solution.cpp


/README.md:
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1 | # GoldmanSachs-Coding-Challenge
2 | The problems (and my solutions to them) for my hacker rank assessment for the Goldman Sachs Software Engineering Internship for 2019 Summer
3 | 


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/Faulty Keyboard: Problem Statement:
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 1 | The 'a' key on the keyboard is not working correctly. Instead of typing 'a' or 'A', it toggles the CapsLock. 
 2 | Return the value of a string that is typed into a keyboard on such a faulty keyboard.
 3 | Note: If shift is pressed when CapsLock is on characters will be printed in lower case
 4 | 
 5 | e.g. 
 6 | Input: "Help, my keyboard is not working"
 7 | Output: "Help, my keyboRD IS NOT WORKING"
 8 | 
 9 | Input: "Hi my name is Adam Levine"
10 | Output: "Hi my nME IS dM lEVINE"
11 | 


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/Faulty-Keyboard:Solution.cpp:
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 1 | //Input and output was handled by Hacker Rank
 2 | //Testees had to only complete a single function that was passed in the string typed in and would return the output on the faulty keyboard
 3 | #incude <cctype.h> //Extra include statement required for islower, toupper etc. functions
 4 | 
 5 | string faultyKeyboard(string input)
 6 | {
 7 |   bool CapsLockOn = false;
 8 |   
 9 |   for (int i  = 0; input[i] != '\0';)
10 |   {
11 |     if (input[i] == 'a' || input[i] == 'A')
12 |     {
13 |       CapsLockOn = ! CapsLockOn;
14 |       input.erase(i, 1);
15 |       continue;
16 |     }
17 |     
18 |     if (CapsLockOn)
19 |     {   
20 |       if (islower(input[i]))
21 |         input[i] = toupper(input[i]);
22 |       else
23 |         input[i] = tolower(input[i]);
24 |     }
25 |     
26 |     i++;
27 |   }
28 |   
29 |   return input;
30 | }
31 | 


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/College Applications: Problem Statement:
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 1 | In country X, colleges pick students strictly based on their scores i.e. students with higher scores get first pick. 
 2 | All students have a list of preferences of colleges that they would like to attend, and if on their turn, the number
 3 | of seats left in their top choice is 0, they apply to their next choice - so on and so forth, in case none of the 
 4 | colleges on a student's preference list has seats left (on their turn), the student doesn't go to college.
 5 | Colleges have a fixed number of seats.
 6 | 
 7 | The number of students, their test scores, the number of colleges, the number of seats available at each college
 8 | and the preference list of every student will be provided.
 9 | 
10 | Input:
11 | NumberOfStudents
12 | Score1
13 | Score2
14 | ...
15 | NumberOfColleges
16 | Seats available at College 1
17 | Seats available at College 2
18 | ...
19 | NumberOfPreferencesInPrefenceList
20 | CollegePick1 CollegePick2 ...
21 | CollegePick1 CollegePick2 ...
22 | ...
23 | 


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/CollegeApps-Solution.cpp:
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 1 | // Input and output was handled by Hacker Rank
 2 | // Testees had to only complete a single function that was passed in: vector<int> collegeSeatsArray, vector<int> studentScoresArray,
 3 | // vector<vector<int>> studentCollegePreferencesArray
 4 | // The indices of the vector<int> collegeSeatsArray indicate the college number - used to reference the college in the
 5 | // studentCollegePreferencesArray. The indices of the studentScoresArray correspond to their corresponding preferences vector in the 
 6 | // studentCollegePreferencesArray. The results had to be returned in a vector<int> where the first element the number of seats left,
 7 | // and the second element indicated the number of students who didn't go to college
 8 | // Each student only gets allocated to one college. 
 9 | 
10 | // Helper functions
11 | int sumElements(vector<int> vec)
12 | {
13 |   int sum = 0;
14 |   for (int i = 0; i < vec.size(); i++)
15 |     sum += vec[i];
16 |   return sum;
17 | }
18 | 
19 | vector<int> uniqueSort(vector<int> vec)
20 | {
21 |   sort(vec.begin(), vec.end());
22 |   vec.erase(unique(vec.begin(), vec.end()), vec.end());
23 |   return vec;
24 | }
25 | 
26 | // The method used in this function ensures that in cases where students have the same scores, the student whose score
27 | // was mentioed earlier in the array will get priority
28 | vector<int> allocate(vector<int> collegeSeatsArray, vector<int> studentScoresArray, vector<vector<int>> studentCollegePreferencesArray)
29 | {
30 |   int seatsLeft = sumElements(collegeSeatsArray);
31 |   int studentsUnallocated = studentScoresArray.size()'
32 |     
33 |   unordered_map<string, vector<vector<int>>> scoresAndPreferences;
34 |   for (int i = 0; i < studentScoresArray.size(); i++)
35 |   {
36 |     if (scoresAndPreferences.find(studentScoresArray[i]) != scoresAndPreferences.end())
37 |       scoresAndPreferences[studentScoresArray[i]] = vector<vector<int>> preferences {studentCollegePreferencesArray[i]};
38 |     else
39 |     {
40 |       vector<vector<int>> preferences = scoresAndPreferences[studentScoresArray[i]];
41 |       preferences.push_back(studentCollegePreferencesArray[i]);
42 |       scoresAndPreferences[studentScoresArray[i]] = preferences;
43 |     }
44 |   }
45 |   
46 |   studentScoresArray = uniqueSort(studentScoresArray);
47 |   
48 |   for (int i = 0; i < studentScoresArray.size(); i++)
49 |   {
50 |     vector<vector<int>> currentStudentPreferences = scoresAndPreferences[studentScoresArray[i]];
51 |     for (int j = 0; j < currentStudentPreferences.size(); j++)
52 |       for (int k = 0; k < currentStudentPreferences[j].size(); k++)
53 |       {
54 |         if (currentStudentPreferences[j][k] > 0)
55 |         {
56 |           currentStudentPreferences[j][k]--;
57 |           studentsUnallocated--;
58 |           seatsLeft--;
59 |           break;
60 |         }
61 |       }
62 |   }
63 |   
64 |   return vector<int> results {seatsLeft, studentsUnallocated};
65 | }
66 | 


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