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.
class PerfectSquares:
    def solve(self,numelements,elements):
        notperf = []
        for num in elements:
            if num<0:
                notperf.append(num)
                continue
            root = (num*1.0)**(0.5)
            if root%1!=0: notperf.append(num)
        return max(notperf)
if __name__ == "__main__":
    numelements = int(raw_input())
    elements = map(int,raw_input().split(" "))
    ps = PerfectSquares()
    print ps.solve(numelements,elements)