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 IsPerfectSq(n):
    x = n**0.5
    if int(x) == x:
        return True
    else:
        return False

def GetLargestNotPerfect(arr):
    max_val = 0
    for i in arr:
        if int(i) > 0 and not IsPerfectSq(int(i)):
            if max_val == 0:
                max_val = int(i)
            if int(i) > max_val:
                max_val = int(i)
        elif int(i) < 0:
            if max_val == 0:
                max_val = int(i)
            if int(i) > max_val:
                max_val = int(i)

    return max_val

def main():
    n = int(raw_input())
    arr = raw_input().split()

    print GetLargestNotPerfect(arr)

main()
