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 sys, math

DEBUG = False

def ni():
    return int(input())
def nia(): 
    return list(map(int,input().split()))

def log(x):
    if (DEBUG):
        print(x)

if DEBUG: 
    sys.stdin = open('a.in')    

n = ni()
a = nia()

log(n)
log(a)

a.sort(reverse=True)

def isPerfect(n):
    if (n < 0):
        return True
    n2 = math.sqrt(n)
    n2int = int(n2)
    return n2int != n2

for i in a:
    if isPerfect(i):
        print(i)
        sys.exit()