#include <stdio.h>
#include <math.h>
int main(){
    unsigned int lightbulbs;

    while(scanf("%u", &lightbulbs)==1){
        if(lightbulbs==0)
            break;

        if(((unsigned int)sqrt(lightbulbs))*((unsigned int)sqrt(lightbulbs))==lightbulbs)
            printf("yes\n");
        else
            printf("no\n");

    }
    return 0;
}