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.
def is_square(n):
    start = 0
    end = n
    while start < end:
        mid = (start + end + 1) / 2
        if mid * mid <= n:
            start = mid
        else:
            end = mid - 1
    return start * start == n


def solution():
    n = int(raw_input().strip())
    arr = list(map(int, raw_input().strip().split()))
    arr.sort()
    for i in range(n)[::-1]:
        if not is_square(arr[i]):
            return arr[i]
    return


if __name__ == '__main__':
    print solution()