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() {
  int n, m = 0, s, a = 0, b = 0, j = -1000001;
  cin >> n;
  int x[n];
  for (int i = 0; i < n; i++) cin >> x[i];
  for (int i = 0; i < n; i++) {
    if (x[i] < 0) {
      b = x[i];
      x[i] = sqrt(x[i] * x[i]);
    } else
      b = 0;
    s = sqrt(x[i]);
    if (s * s != x[i]) {
      a = 1;
    }
    if (b != 0) {
      x[i] = b;
    }
    if (x[i] >= m && a != 0) {
      m = x[i];
    }
    if (x[i] < 0 && x[i] >= j && a != 0 or x[i] == -1) j = x[i];
    a = 0;
  }
  if (m == 0)
    cout << j;
  else
    cout << m;
}
