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
n = input()

firstline = input().strip()

narray = firstline.split()

max_num = -9999999

for number in narray:
    num = int(number)
    if num >= 0:
        val = math.sqrt(num)
        if int(val) * int(val) != num:
            if num > max_num:
                max_num = num
    else:
       if num > max_num:
            max_num = num 

print(max_num)