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.
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/**
 *
 * @author VEDANT
 */
//Codeforces
import java.util.*;
public class Perfect_Squares {
    public static void main(String args[]){
        Scanner in=new Scanner(System.in);
        int n=in.nextInt();
        int a[]=new int[n];
        for(int i=0;i<n;i++){
            a[i]=in.nextInt();
        }
            Arrays.sort(a);
            for(int c=n-1;c>=0;c--){
            double k=Math.sqrt((double)a[c]);
            int t=(int)k;
            
            if((k-t)!=0){
               System.out.println(a[c]);
               break;
            }
        }
    }
}
