为什么这样会WA

#include<iostream>
#include<cmath>
using namespace std;
double k, l;
int main()
{
	cin >> k >> l;
	if (floor(log(l) / log(k)) == ceil(log(l) / log(k)))
		cout << "YES\n" << log(l) / log(k) - 1;
	else cout << "NO";
	return 0;
}