import java.util.Scanner;

public class Main {

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

		long H = sc.nextLong();
		// Hのlog2をとる
		double val = Math.log(H) / Math.log(2);
		val = Math.floor(val);

		long cnt = 0;

		for (int i = 0; i <= val; i++) {
			cnt += Math.pow(2, i);
		}

		System.out.println(cnt);
		sc.close();
	}
}

/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