#include <iostream>
#include <cmath>
using namespace std;

int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);

    long long n;
    while(cin >> n && n)
    {
        long long sq = sqrt(n);
        if(sq * sq == n) ///Perfect square
            cout << "yes\n";
        else
            cout << "no\n";
    };

    return 0;
};