import java.util.*;
public class Main {
  public static void main(String[] args){
    Scanner sc = new Scanner(System.in);
    long h = sc.nextLong();
    int count = 0;
    long ans = 0;

    while(h>0){
      h = h/2;
      count++;
    }
    
    for(int i = 0 ; i < count ; ++i){
        ans += (long)Math.pow(2,i);
    }
        
    System.out.println(ans);

  }
}
/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