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 n, i, rez, x;
set<int> S;
int main() {
  ios::sync_with_stdio(false);
  for (i = 0; i * i <= 1000000; i++) S.insert(i * i);
  cin >> n;
  rez = -1000000;
  for (i = 1; i <= n; i++) {
    cin >> x;
    if (S.find(x) == S.end()) rez = max(rez, x);
  }
  cout << rez << "\n";
  return 0;
}
