Euler 003 Javascript Solution

Largest prime factor

Problem

https://projecteuler.net/problem=3

The prime factors of 13195 are 5, 7, 13 and 29.

What is the largest prime factor of the number 600851475143?

Answer: 6857

Solution

solution003.js

module.exports = {
  answer : () => {
    answer = 2;
    point = 3;
    divisor = 600851475143;

    while(divisor != 1) {
      while( (divisor % 2) == 0) { divisor /= 2; }
      while ((divisor % point) == 0) {
        answer = point;
        divisor /= point;
      }
      point += 2;
    }
    return answer;
  }
};

See Also