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
mp = 0
mo = 0
n = int(input())
a = input().split()
a = [int (i) for i in a]
ot = []
a = sorted(a)
for j in range(len(a)):
    if a[j] < 0:
        ot.append(a[j])
    else:
        break
a.reverse()
if len(ot) > 0:
    mo = max(ot)
for i in range(len(a)):
    if a[i] > 0:
        s = math.sqrt(abs(a[i]))
        k = int (s)
        if s != k:
            mp = a[i]
            break
if mp != 0:
    print(mp)
else:
    print(mo)