2427. Number of Common Factors

Given two positive integers a and b, return the number of common factors of a and b.

An integer x is a common factor of a and b if x divides both a and b.

class Solution {
public:
    int commonFactors(int a, int b) {
        int g = __gcd(a,b);
        int res = 0;
        for(int i = 1; i <= sqrt(g); i++) {
            if(g % i) continue;
            res += 1;
            if(i * i != g) res += 1;
        }
        return res;
    }
};