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>
const long long int INF = 2e9 + 999, MOD = 1e9 + 7, MAXN = 100001;
const long double EPS = 0.000001;
using namespace std;
bool sq(int x) {
  int a = (int)(sqrt(x) + EPS);
  if (a * a != x) {
    return 0;
  }
  return 1;
}
int main() {
  int n;
  cin >> n;
  vector<int> a(n);
  for (int i = 0; i < n; ++i) {
    cin >> a[i];
  }
  int ans = -INF;
  for (int i = 0; i < n; ++i) {
    if (!sq(a[i])) {
      ans = max(ans, a[i]);
    }
  }
  cout << ans;
  return 0;
}
