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.
n = int(input())

lst = []
for x in input().split():
    lst.append(int(x))

max_n = - 10 ** 6 - 1
for x in lst:
    if x >= 0:
        k1 = -1
        k2 = 10 ** 6 + 1
        while k2 - k1 > 1:
            k = (k1 + k2) // 2
            if k ** 2 >= x:
                k2 = k
            else:
                k1 = k
        if k2 ** 2 != x:
            max_n = max(max_n, x)
    else:
        max_n = max(max_n, x)

print(max_n)
