Given an array a1, a2, ..., an of n integers, find the largest number in the array that is not a perfect square.

A number x is said to be a perfect square if there exists an integer y such that x = y2.

Input

The first line contains a single integer n (1 ≤ n ≤ 1000) — the number of elements in the array.

The second line contains n integers a1, a2, ..., an ( - 106 ≤ ai ≤ 106) — the elements of the array.

It is guaranteed that at least one element of the array is not a perfect square.

Output

Print the largest number in the array which is not a perfect square. It is guaranteed that an answer always exists.

Examples

Input

2
4 2


Output

2


Input

8
1 2 4 8 16 32 64 576


Output

32

Note

In the first sample case, 4 is a perfect square, so the largest number in the array that is not a perfect square is 2.
import java.util.*;
import java.lang.*;
import java.io.*;


 public class PerfectSquare{
	 static int ff(int x){
		 int a = (int)Math.sqrt(x);
		 if( a*a != x){
			 return a;
		 }
		 else return -1;
	 }
    public static void main(String args[]){
		
		Scanner s = new Scanner(System.in);
        //boolean w = false;
        int n  = s.nextInt();
		
		long max = -1000000L;
		int x;
		
	//	long [] N = new long[n];
		//boolean e = true;
		for(int i = 0 ; i < n; i++){
				x = s.nextInt();
					if(ff(x) != -1){
						
						if(max < x){
							max = x;
						}
					}
				
			}
		System.out.println(max);
	}
}