UVa 10110 - Light, more light

// UVa 10110 - Light, more light
#include <iostream>
#include <cmath>

using namespace std;

int main() {
	unsigned long long n;
	cin >> n;
	while (n != 0) {

		if (sqrt(n) == int(sqrt(n)))
			cout << "yes" << endl;
		else
			cout << "no" << endl;

		cin >> n;
	}
	return 0;
}