import java.util.*;
public class Main{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        // 整数の入力
        double h = sc.nextDouble();
        double ans = 1;
        double now = 1;
        double nowmax = Math.pow(2,now) -1;
     	while(h >  nowmax){
          ans += Math.pow(2,now);
          now += 1;
          nowmax = Math.pow(2,now) -1;
        }
      System.out.println((long)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