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 math

def perfect_square( num ):
        if num < 0:
                return False
        num_sqrt = int( math.sqrt( num ) )
        return True if num_sqrt * num_sqrt == num else False


n = int(input())

ar = list( map( int,input().split() ) )

ans = int(-1e7)

for i in range( n ):
        if not perfect_square( ar[i] ):
                ans = max( ans, ar[i] )
        
print( ans )