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.
#include <bits/stdc++.h>
using namespace std;
int main() {
  long int num, a[1001], b[1001], j, i;
  cin >> num;
  for (i = 0; i < num; i++) {
    scanf("%ld", &a[i]);
  }
  sort(a, a + num);
  for (i = 0; i < 1000; i++) {
    b[i] = (i + 1) * (i + 1);
  }
  for (j = num - 1; j >= 0; j--) {
    if (binary_search(b, b + 1000, a[j]) == 0 && a[j] != 0) {
      printf("%ld", a[j]);
      break;
    }
  }
}
