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


class CodeforcesTask914ASolution:
    def __init__(self):
        self.result = ''
        self.n = 0
        self.array = []

    def read_input(self):
        self.n = int(input())
        self.array = [int(x) for x in input().split(" ")]

    def process_task(self):
        not_perfect_square = [x for x in [y for y in self.array if y >= 0] if not math.sqrt(x).is_integer()]
        not_perfect_square += [y for y in self.array if y < 0]
        not_perfect_square.sort(reverse=True)
        self.result = str(not_perfect_square[0])

    def get_result(self):
        return self.result


if __name__ == "__main__":
    Solution = CodeforcesTask914ASolution()
    Solution.read_input()
    Solution.process_task()
    print(Solution.get_result())
