<image> <image>

*The two images are equivalent, feel free to use either one.

Input

The input contains a single integer a (-100 ≤ a ≤ 100).

Output

Output the result – an integer number.

Example

Input


1


Output


1
/**
 *    author:  tourist
 *    created: 01.04.2021 17:51:55       
**/
#include <bits/stdc++.h>

using namespace std;

int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  int x;
  cin >> x;
  cout << 2 - x * x << '\n';
  return 0;
}
