import java.util.Scanner;

class Main {
  public static void main(String[] args) {
    
    Scanner sc = new Scanner(System.in);
    long H = sc.nextLong();
    long Attack = 0;
    long Monster = 1;
    
    while (H > 0) {
      Attack += Monster;
      H /= 2;
      Monster *= 2;
    }

    System.out.println(Attack);
    
  }
}
/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