└── 05_project_euler
    ├── 01-problem-multiples-of-3-and-5.js
    ├── 02_even_fibonacci_numbers.py
    └── 04-problem-largest-palindrome-product.js


/05_project_euler/01-problem-multiples-of-3-and-5.js:
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 1 | // Problem 1: Multiples of 3 and 5
 2 | // If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9. The sum of these multiples is 23.
 3 | // Find the sum of all the multiples of 3 or 5 below the provided parameter value number.
 4 | 
 5 | function multiplesOf3and5(number) {
 6 |   let sum = 0;  
 7 |   for (let i = 0; i < number; i++) {
 8 |     if(i % 3 === 0 || i % 5 === 0) {
 9 |       sum +=i
10 |     }
11 |   }
12 |   return sum;
13 | }
14 | 
15 | multiplesOf3and5(1000);


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/05_project_euler/02_even_fibonacci_numbers.py:
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 1 | number1 = 1
 2 | number2 = 2
 3 | summation = 0
 4 | while number2 < 4000000:
 5 |     summation += number2
 6 |     number1, number2 = number2, number1 + number2
 7 |     number1, number2 = number2, number1 + number2
 8 |     number1, number2 = number2, number1 + number2
 9 | print(summation)
10 | 


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/05_project_euler/04-problem-largest-palindrome-product.js:
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 1 | function largestPalindromeProduct(n) {
 2 |   // Good luck!  
 3 |   let lowerBound = Math.pow(10, n - 1);
 4 |   let upperBound = Math.pow(10, n) - 1;
 5 |   let maxPalindrome = 0;
 6 | 
 7 |   for (let i = Math.pow(10, n - 2) * 11; i <= upperBound; i = i + 11) {
 8 |     for (let j = lowerBound; j <= upperBound; j++) {
 9 |       let number = i * j;
10 |       if (number > maxPalindrome) {
11 |         if (isNumPalindrome(number)) {
12 |           maxPalindrome = number;
13 |         }
14 |       }
15 |     }
16 |   }
17 |   return maxPalindrome;   
18 | }
19 | 
20 | function isNumPalindrome(num)
21 | {
22 |   let textNum = num.toString();
23 |   let left = 0;
24 |   let textNumLength = textNum.length - 1;
25 |   // Keep comparing characters while they are same  
26 |   while (left < textNumLength) {
27 |     if (textNum[left] != textNum[textNumLength]) {
28 |       return false;
29 |     }
30 |     left++;
31 |     textNumLength--;
32 |   }
33 |   return true;
34 | }
35 | 
36 | largestPalindromeProduct(3);
37 | 


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