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 = int(input())
l = list(map(int, input().split()))
def kd(n):
    if n < 0:
        n*=-1
    ans = {1, n}
    for i in range(2, (int(n**0.5)+1)):
        if n % i == 0:
            ans|={i, n//i}
    return ans
ma = -10**12
for j in l:
    if j == 0:
        continue
    elif j < 0:
        if j > ma:
            ma = j
    else:
        if len(kd(j)) % 2 == 0:
            if j > ma:
                ma = j
print(ma)        
