import java.util.Scanner;

public class Main {

    private static long solve(long H) {
        if (H <= 1L) {
            return 1L;
        } else {
            return 2L * solve((long)Math.floor(H / (double)2)) + 1L;
        }
    }

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

        long H = sc.nextLong();
        // ツリーのノード数分だけ攻撃する必要がある.
        System.out.println(solve(H));
    }
}

/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