import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner s = new Scanner(System.in);
        long H = Long.parseLong(s.next());
        System.out.println(atack(H));
    }

    // 再帰でやるとこう
    static long atack(long h) {
        if (h == 1) {
            return 1;
        }
        return atack(h / 2) * 2 + 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