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
import sys


def scan():
    return list(map(int, sys.stdin.readline().strip().split()))


def solution():
    # for _ in range(int(input())):
    # n = int(input())
    n = int(input())
    a = scan()
    a.sort()
    m = 0
    for i in a:
        if i < 0:
            m = i
            continue
        d = math.sqrt(i)
        if d != int(d):
            m = i
    print(m)


if __name__ == '__main__':
    solution()
