<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.util.*;

public class F_Math
{
    public static void main(String[] args) throws IOException
    {
        int num = readInt();
        System.out.println(2-num*num);
    }

    static BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    static StringTokenizer st;

    static long readLong() throws IOException
    {
        while (st == null || !st.hasMoreTokens())
        {
            st = new StringTokenizer(br.readLine());
        }
        return Long.parseLong(st.nextToken());
    }

    static int readInt() throws IOException
    {
        while (st == null || !st.hasMoreTokens())
        {
            st = new StringTokenizer(br.readLine());
        }
        return Integer.parseInt(st.nextToken());
    }
}