Light More Light/문보창

~cpp 
// no10110 - Light, more Light
#include <iostream>
#include <cmath>
using namespace std;
int main()
{	
	unsigned int n;
	while (cin >> n)
	{
		if (n == 0)
			break;
		if (int(sqrt(n)) == double(sqrt(n)))
			cout << "yes\n";
		else
			cout << "no\n";
	}
	return 0;
}