<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 Mango {
	
	public static void main(String[] args) throws Exception {
	Scanner sc = new Scanner(System.in);
	long x = sc.nextLong();
	System.out.println((long)(2-Math.pow(x, 2)));
	}
}
