<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.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.io.*;
import java.util.ArrayList;

public class Math {
    public static void main(String[] args) throws IOException {
//                        BufferedReader f = new BufferedReader(new FileReader("C:\\Users\\Owner\\CF2021\\src\\test.in"));
//        PrintWriter out = new PrintWriter(new BufferedWriter(new FileWriter("C:\\Users\\Owner\\CF2021\\src\\test.out")));
        BufferedReader f = new BufferedReader(new InputStreamReader(System.in));
        PrintWriter out = new PrintWriter(System.out);
        String str = f.readLine();
        int num = Integer.parseInt(str);
        out.println((2 - (num * num)));

        f.close();

        out.close();

    }
}
