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 isqrt(n):
    if n < 0:
        return None
    elif 0 <= n <= 1:
        return n
    x = n // 2
    seen = set([x])
    while x * x != n:
        x = (x + (n // x)) // 2
        if x in seen:
            return None
        seen.add(x)
    return x

def is_square(n):
    return isqrt(n) is not None

n = int(input())
a = [int(v) for v in input().split()]

print(max(v for v in a if not is_square(v)))
