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.
# list(map(int, input().split()))
from math import sqrt
n = int(input())
ans = -1e9
z = list(map(int, input().split()))
for t in z:
    if (t < 0):
        ans = max(t, ans)
    else:
        p = int(sqrt(t))
        while (p + 1) * (p + 1) <= t:
            p += 1
        while p * p > t:
            p -= 1
        if p * p != t:
            ans = max(ans, t)
print(ans)

