import java.util.*;

 class Main
{
	public static void main(String[] args)
	{
		Scanner sc = new Scanner(System.in);
		long n = sc.nextLong();
		int x = (int)(Math.log(n)/Math.log(2));
	    System.out.println((long)(Math.pow(2,x+1)-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