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.
n=input()
from math import sqrt
lst=map(int,raw_input().split())

val=10000000000000
lst.sort()
for i in range(0,n):
  if lst[i]<0:
    val2=lst[i]
for i in range(0,n):
  if lst[i]==0:
    lst[i]=-1000000000000
  if lst[i]>0 and int(sqrt(abs(lst[i])))!=sqrt(abs(lst[i])):
    val=lst[i]
  
  if 1==2:
    val=1
    
if val==10000000000000 or val==0:
  print val2
else:
  print val
  
  
