import java.util.*;
public class Main{

  static void findAns(long n,long ans,int count){

    if(n>1){
      ans+=Math.pow(2,count);
      ++count;
      findAns(n/2,ans,count);
    }
    else{
      ans+=Math.pow(2,count);
      System.out.println(ans);
    }
  }

  public static void main(String args[]){
    Scanner sc=new Scanner(System.in);
    long n=sc.nextLong();
    long ans=0;
    findAns(n,ans,0);
  }
}

/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