import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class Main {

	static BufferedReader reader;
	//static field here
	
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		reader = new BufferedReader(new InputStreamReader(System.in));
		//code here
		String[] strings = readLine();
		long H = Long.parseLong(strings[0]);
		long c = 0;
		while(H>0) {
			H/=2;
			c*=2;
			c++;
		}
		print(c);
		
		//String[] s = readLine();
		//print(num);
	}
	
	//functions here
	//note that all methods should be STATIC

	private static String[] readLine(){
		try{
			return reader.readLine().split(" ");
		}catch(Exception e){
			e.printStackTrace();
			return new String[]{e.getMessage()};
		}
	}
	private static void print(Object o){
		System.out.println(o);
	}
	private static void print(){
		System.out.println();
	}
}
/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