import java.util.Scanner;

public class Main {
	public static void main(String[] args) {

		try (Scanner sc = new Scanner(System.in)) {
			long h = sc.nextLong();

			long cnt = 1;
			while (cnt <= h) {
				cnt *= 2;
			}

			System.out.println(cnt - 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