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.
# -*- coding: utf-8 -*-
"""
Created on Sun Apr 12 00:21:22 2020

@author: alexi
"""



#https://codeforces.com/problemset/problem/914/A --- Alexis Galvan

import math

def perfect_square():
    
    total = int(input())
    
    numbers = list(map(int, input().split()))
    
    output = min(numbers)
    
    for i in range(len(numbers)):
        if numbers[i] < 0:
            if numbers[i] > output:
                output = numbers[i]
        else: 
            temp = int(math.sqrt(numbers[i]))
            if temp*temp != numbers[i]:
                if numbers[i] > output:
                    output = numbers[i]

                
    return output

A = perfect_square()
print(A)
    