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.
from math import sqrt
s=int(raw_input())
L=map(int,raw_input().split(' '))
S=0
for i in L:
    if (i>0):
        if ((not(sqrt(i) == int(sqrt(i)))) and (i>S) ) :
            S=i

if not S:
    i=0
    while(1):
        if (L[i]<0):
            S=L[i]
            break;
        i+=1
    for i in L:
        if ((i<0) and (i>S)):
            S=i
print(S)
