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;
long long int s1, s2, d, f = 0, p = 0, b, m, i, c = 0, ans, e, o;
int t;
string h, k;
long long int x[100010];
int main() {
  int n;
  cin >> n;
  for (int q = 0; q < n; ++q) {
    cin >> x[q];
  }
  sort(x, x + n);
  for (int q = n - 1; q >= 0; q--) {
    int t = sqrt(x[q]);
    if (x[q] < 0) {
      cout << x[q];
      return 0;
    }
    if (t * t != x[q]) {
      cout << x[q];
      return 0;
    }
  }
  return 0;
}
