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 Sat Aug 15 14:57:41 2020

@author: Manan Tyagi

"""
import math
def ips(n):
    k=math.sqrt(n)
    return k==math.floor(k)
    
import sys
#input=sys.stdin.buffer.readline
t=int(input())
a=sorted(list(map(int,input().split())),reverse=True)
for i in range(t):
    if a[i]>=0:
        if not ips(a[i]):
           #print(2)
            print(a[i])
            break
    else:
        print(a[i])
        break

    
    
            
        
   