import java.util.Arrays;
import java.util.Scanner;
public class Main{
	public static void main(String[]args) {
		Scanner sc=new Scanner(System.in);
		long n=sc.nextLong();
		long c=1;
		long sum=0;
		while(n!=0) {
			n=n/2;
			sum=sum+c;
			c=c*2;
		}
		System.out.println(sum);  
		
	}
	
} import java.util.Arrays; Arrays java.util import java.util.Scanner; Scanner java.util public class Main{
	public static void main(String[]args) {
		Scanner sc=new Scanner(System.in);
		long n=sc.nextLong();
		long c=1;
		long sum=0;
		while(n!=0) {
			n=n/2;
			sum=sum+c;
			c=c*2;
		}
		System.out.println(sum);  
		
	}
	
} Main public static void main(String[]args) {
		Scanner sc=new Scanner(System.in);
		long n=sc.nextLong();
		long c=1;
		long sum=0;
		while(n!=0) {
			n=n/2;
			sum=sum+c;
			c=c*2;
		}
		System.out.println(sum);  
		
	} main {
		Scanner sc=new Scanner(System.in);
		long n=sc.nextLong();
		long c=1;
		long sum=0;
		while(n!=0) {
			n=n/2;
			sum=sum+c;
			c=c*2;
		}
		System.out.println(sum);  
		
	} Scanner sc=new Scanner(System.in); sc new Scanner(System.in) long n=sc.nextLong(); n sc.nextLong() sc.nextLong sc long c=1; c 1 long sum=0; sum 0 while(n!=0) {
			n=n/2;
			sum=sum+c;
			c=c*2;
		} n!=0 n 0 {
			n=n/2;
			sum=sum+c;
			c=c*2;
		} n=n/2 n n/2 n 2 sum=sum+c sum sum+c sum c c=c*2 c c*2 c 2 System.out.println(sum) System.out.println System.out System System.out sum String[]args args public class Main{
	public static void main(String[]args) {
		Scanner sc=new Scanner(System.in);
		long n=sc.nextLong();
		long c=1;
		long sum=0;
		while(n!=0) {
			n=n/2;
			sum=sum+c;
			c=c*2;
		}
		System.out.println(sum);  
		
	}
	
} public class Main{
	public static void main(String[]args) {
		Scanner sc=new Scanner(System.in);
		long n=sc.nextLong();
		long c=1;
		long sum=0;
		while(n!=0) {
			n=n/2;
			sum=sum+c;
			c=c*2;
		}
		System.out.println(sum);  
		
	}
	
} Main
import java.util.Arrays;
import java.util.Scanner;
public class Main{
	public static void main(String[]args) {
		Scanner sc=new Scanner(System.in);
		long n=sc.nextLong();
		long c=1;
		long sum=0;
		while(n!=0) {
			n=n/2;
			sum=sum+c;
			c=c*2;
		}
		System.out.println(sum);  
		
	}
	
}