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.Scanner;

/*
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/**
 *
 * @author rn-sshawish
 */
public class Contest914A {
    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        int n = input.nextInt();
        int max = Integer.MIN_VALUE;
        for (int i = 0; i < n; i++) {
             int value = input.nextInt();
            if (value < 0) {
                max = Math.max(max, value);
            }
            double x1 = Math.sqrt(value);
            double x2 = (int)x1;
            if (x1 > x2 || value == 2) {
               max = Math.max(max, value);
            }
        }
        System.out.println(max);
    }
}


