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
x = (input())
maxi = None
mini = None
min = None
max = 0
str = input()
str = str.split()
strp = list()
strn = list()
for i in range (len(str)):
    str[i] = int(str[i])
    if str[i]>=0:
        strp.append(str[i])
    else:
        strn.append(str[i])
for i in range (len(strp)):
    res = math.sqrt(int(strp[i]))
    if(res > max and strp[i]%(math.sqrt(int(strp[i])))!=0):
        maxi = i
        max = res
for i in range (len(strn)):
    strn[i] *= -1
for i in range (len(strn)):
    res = math.sqrt(int(strn[i]))
    if(mini == None or res < min and (strn[i]%(math.sqrt(int(strn[i])))!=0)):
        mini = i
        min = res
if(min != None):
    strn[mini]*=-1
if(maxi == None):
    print(strn[mini])
else:
    print(strp[maxi])