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 Jan 20 21:07:16 2018

@author: dell
"""
import math
def maxnum(length,array):
    li=[]
    for i in range(length):
        if(array[i]>0):           
            if((array[i]/math.sqrt(array[i]))!=int(math.sqrt(array[i]))):
                li.append(array[i])
        elif(array[i]==0):
            array[i]=0
        else:
            li.append(array[i])

    return max(li)
            
a=input()



inp=map(int,raw_input().split())
   
print maxnum(a,inp)
        
