import java.util.Scanner;

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

	long H = sc.nextLong();

	long n = 0;
	do {
	    H = H / 2;
	    n++;
	} while (H > 0);

	long ans = 1;
	long floor = 1;
	for (long i = 1; i < n; i++) {
	    ans += floor * 2;
	    floor *= 2;
	}

	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