#include<iostream>
#include<bits/stdc++.h>
using namespace std;
int main()
{
    long long int n,c;
    int i,x;
    while(cin>>n && n)
    {
        x=sqrt(n);
        if(x*x==n)  cout<<"yes"<<endl;
        else cout<<"no"<<endl;
    }
    return 0;
}