import java.util.*;
public class Main {
	public static void main(String[] args){
      Scanner sc = new Scanner(System.in);
      long H = sc.nextLong();
      long count =0;
      if(H==1){
        System.out.println(1);
      }else{
      while(true){
        H/=2;
        count++;
        if(H==1){
          break;
        }
      }
      long ans =1+2*((long)Math.pow(2,count)-1);
      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