import java.util.*;
public class Main {
  
  public static double cal(double h){
    if(h == 1.0){
      return 1.0;
    }
    else
    {
      return cal(Math.floor(h/2))*2 + 1.0;
    }
  }
  
  public static void main(String[] args){
    Scanner sc = new Scanner(System.in);
	double h = sc.nextDouble();
    System.out.println(String.format("%.0f", cal(h)));
  }
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz