<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
    import java.util.Scanner;
    public class Solution {
     
        public static void main(String[] args) {
            Scanner sc = new Scanner(System.in);
            
            int t;
            
            t = sc.nextInt();
            
            System.out.println(2 - t * t);
        }
    }