import java.util.*;
public class Main
{
  public static void main(String[] args)
  {
    Scanner ob=new Scanner(System.in);
    long h=ob.nextLong();
    long k=1;
    long c=0;
    while(h>0)
    {
      c=c+k;
      h=h/2;
      k=k*2;
    }
    System.out.println(c);
  }
}
/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