UVA 10110

#include<iostream>
#include<cmath>
using namespace std;
int main()
{
    long long n;
    while(cin>>n)
    {
        if(n==0)break;
        long long flag;
        flag=(int)sqrt((double)n);
        if(flag*flag==n)
            cout<<"yes"<<endl;
        else
            cout<<"no"<<endl;
    }
    return 0;
}