Largest Coprime Divisor

• Time : $O(sqrt(A)*log(min(B,factor(A)))$
• Space : $O(1)$

int Solution::cpFact(int A, int B) {
    int res = -1;
    for(int i = 1; i <= sqrt(A); i++) {
        if(A % i) continue;
        int l = i, r = A / i;
        if(__gcd(l,B) == 1) res = l;
        if(__gcd(r,B) == 1) return r;
    }
    return res;
}