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.
from math import sqrt


def solve(a, n):
    max_val = -100000000000000
    for i in a:
        if i < 0:
            if i > max_val:
                max_val = i
        elif not sqrt(i).is_integer() and i > max_val:
            max_val = i
    return max_val


def main():
    # vars = list(map(int, input().split(" ")))
    n = int(input())
    a = list(map(int, input().split(" ")))
    # b = list(map(int, input().split(" ")))
    # for i in range(n):
    #     arr.append(list(map(int, list(input()))))
    print(solve(a, n))


main()
