import java.util.*;


class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        
        Long H = sc.nextLong();
        int count = 0;
        Long ans = 0L;
        while (H>0) {
            H = H/2;
            ans += (long) Math.pow(2, count++);
        }
        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