import java.util.Scanner;

public class Solution {
    public static void main(String[] args) throws Exception {
        Scanner s = new Scanner(System.in);
        System.out.println("Введите число");
        int myInt = s.nextInt();
        if (myInt>0) System.out.println(myInt*2);
        if (myInt<0) System.out.println(myInt+1);
        if (myInt==0) System.out.println(myInt);
    }
}