count-factors.js

// you can write to stdout for debugging purposes, e.g.
// console.log('this is a debug message');

function solution(N) {
    // write your code in JavaScript (Node.js 8.9.4)
    let i = 1;
    let result = 0;
    while (i < Math.sqrt(N)) {
        if (N % i == 0) {
            result += 2;
        }
        i++;
    }
    if (Math.pow(i, 2) == N) {
        result += 1;
    }
    return result;
}

/*
A positive integer D is a factor of a positive integer N if there exists an integer M such that N = D * M.

For example, 6 is a factor of 24, because M = 4 satisfies the above condition (24 = 6 * 4).

Write a function:

function solution(N);

that, given a positive integer N, returns the number of its factors.

For example, given N = 24, the function should return 8, because 24 has 8 factors, namely 1, 2, 3, 4, 6, 8, 12, 24. There are no other factors of 24.

Write an efficient algorithm for the following assumptions:

N is an integer within the range [1..2,147,483,647].
*/