<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
#include <iostream>
#include <math.h>
using namespace std;
 
int main() {
  int x;
  cin >> x;
  cout << 2-x*x;
  return 0;
}