<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.*;
import java.io.*;
public class mathaf
{
    static BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
    public static void main(String[] args)throws IOException
    {
        int t=Integer.parseInt(in.readLine());
        System.out.println(2-t*t);
    }
}