import java.util.Scanner;
import java.util.Arrays;


class Main{
  public static void main(String args[]){
    Scanner sc = new Scanner(System.in);
    long H = sc.nextLong();

    int i = 0;
    for(i = 1;H > 1;i++){

      H = H/2;
    }


  /*  double N = 0;
    for(int n = 1;n <= i;n++){
      N += Math.pow(2, i-1)-1;
    }*/

  
  //  System.out.println(N);
    System.out.println((long)(Math.pow(2, i-1)+Math.pow(2, i-1)-1));
  }

}

/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