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

n = input()
a = input().split()
best = None
for x in a:
    y = int(x)
    pretendent = None
    if y < 0:
        pretendent = y
    elif math.pow(math.floor(math.sqrt(y)), 2) != y:
        pretendent = y
    if pretendent is not None:
        if best is None:
            best = pretendent
        elif pretendent > best:
            best = pretendent
print(best)
 
