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.
/* package codechef; // don't place package name! */

import java.util.*;
import java.lang.*;
import java.io.*;

/* Name of the class has to be "Main" only if the class is public. */
public class Codechef
{
	public static void main (String[] args) throws java.lang.Exception
	{
	    Scanner sc = new Scanner(System.in);
	    int n = sc.nextInt();
	    
	    int arr[] = new int[n];
	    
	    for(int i=0;i<n;i++)
	        arr[i]=sc.nextInt();
	    
	    Arrays.sort(arr);
	    
	    int ans=Integer.MAX_VALUE;
	    
	    for(int i=n-1;i>=0;i--){
	        double temp = Math.sqrt(arr[i]);
	        
	        if(temp!=(int)temp){
	            ans=arr[i];
	            break;
	        }
	    }
        System.out.print(ans);
	}
}
