<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.*;
public class F_Math 
{
	public static void main(String[] args)throws IOException
	{
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		int n=Integer.parseInt(br.readLine());
		System.out.println(2-(int)Math.pow(n, 2));
	}

}
