<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.io.*;
import java.util.*;
public class math {
	public static void main (String [] args) throws IOException{
	  BufferedReader f = new BufferedReader(new InputStreamReader(System.in));
      PrintWriter out = new PrintWriter(System.out);
    
      StringTokenizer st = new StringTokenizer(f.readLine());
      int x = Integer.parseInt(st.nextToken());
      out.println((int)(2 - Math.pow(x, 2)));
      out.close();
	}
}
