Bob the Penguin wants to find out if a given number is a square number. Will you help him?

Task

Write a program that takes in 1 integer value, A, and output if the value is a square number or not.

Constraints

0 ≤ A ≤ 10,000,000

Input

Your program should read from standard input the following data: The first line contains 1 integer A.

Output

Your program should write to the standard output a string.

Sample Input 1

9

Sample Output 1

yes

Sample Input 2

5

Sample Output 2

no