1. 
/**
* FWP: Ausgewaehlte Probleme aus dem ACM (SS10)
*
* Method: Math
* Problem: 10110 - LightMoreLight
* Accepted: 0.904
* @author Evgeni Pavlidis
*
*/
import java.io.*;
import java.util.*;
import java.math.*;

class Main {

public static void main(String...args) throws Exception
{
BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
long n, i;


while( (n = Long.parseLong(reader.readLine())) != 0)
{
i = (long)Math.pow(Math.floor( Math.sqrt(n) ),2);

if(n == i)
System.out.println("yes");
else
System.out.println("no");
}
}
}