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.io.*;
import java.util.Arrays;


public class Problem1 {

	public static boolean perfectSquare[] = new boolean[1000001];
	
	public static void main(String args[]) throws IOException
	{
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		int n = Integer.parseInt(br.readLine());
		int arr[] = new int[n];
		perfectSquare[0] = true;
		for(int i = 1 ; i*i <= 1000000 ; i++)
		{
			perfectSquare[i*i] = true;
		}
		String ip[] = br.readLine().split(" ");
		for(int i = 0 ; i < n ; i++)
		{
			arr[i] = Integer.parseInt(ip[i]);
		}
		
		Arrays.sort(arr);
		
		for(int i = n-1 ; i >= 0 ; i--)
		{
			if(arr[i] >= 0)
			{
				if(!perfectSquare[arr[i]])
				{
					System.out.println(arr[i]);
					break;
				}
			}
			else
			{
				System.out.println(arr[i]);
				break;
			}
		}
		
	}
}
