[Codility] Lesson10. Prime And Composite Numbers-CountFactors C언어 풀이

int solution(int N) {
    int count = 0, index = 1;
    double rootN = sqrt(N);
    
    while(index < rootN){
        if(N % index == 0)
            count += 2;
        index++;
    }
    if(index == rootN)
        count++;
        
    return count;
}