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.
#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
Created on Sat Jan 20 10:35:27 2018

@author: sayed
"""

import sys

n = int(sys.stdin.readline())
l = [int(elem) for elem in sys.stdin.readline().split()]

def is_not_square(apositiveint):
    if apositiveint < 0:
        return True    
    if apositiveint == 1:
        return False
    if apositiveint == 0:
        return False
    x = apositiveint // 2
    seen = set([x])
    while x * x != apositiveint:
        x = (x + (apositiveint // x)) // 2
        if x in seen: return True
        seen.add(x)
    return False

print(max(filter(is_not_square,l)))