import java.util.Scanner;

public class Main{
  public static void main(String args[]){
    Scanner sc = new Scanner(System.in);
    int a = sc.nextInt();
    int fh = a / 500;
    a = a - (fh * 500); 
    int f = a / 5;
    int ans = (fh * 1000) + (f * 5);
    System.out.println(ans);
  }
} import java.util.Scanner; Scanner java.util public class Main{
  public static void main(String args[]){
    Scanner sc = new Scanner(System.in);
    int a = sc.nextInt();
    int fh = a / 500;
    a = a - (fh * 500); 
    int f = a / 5;
    int ans = (fh * 1000) + (f * 5);
    System.out.println(ans);
  }
} Main public static void main(String args[]){
    Scanner sc = new Scanner(System.in);
    int a = sc.nextInt();
    int fh = a / 500;
    a = a - (fh * 500); 
    int f = a / 5;
    int ans = (fh * 1000) + (f * 5);
    System.out.println(ans);
  } main {
    Scanner sc = new Scanner(System.in);
    int a = sc.nextInt();
    int fh = a / 500;
    a = a - (fh * 500); 
    int f = a / 5;
    int ans = (fh * 1000) + (f * 5);
    System.out.println(ans);
  } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int a = sc.nextInt(); a sc.nextInt() sc.nextInt sc int fh = a / 500; fh a / 500 a 500 a = a - (fh * 500) a a - (fh * 500) a (fh * 500) fh 500 int f = a / 5; f a / 5 a 5 int ans = (fh * 1000) + (f * 5); ans (fh * 1000) + (f * 5) (fh * 1000) fh 1000 (f * 5) f 5 System.out.println(ans) System.out.println System.out System System.out ans String args[] args public class Main{
  public static void main(String args[]){
    Scanner sc = new Scanner(System.in);
    int a = sc.nextInt();
    int fh = a / 500;
    a = a - (fh * 500); 
    int f = a / 5;
    int ans = (fh * 1000) + (f * 5);
    System.out.println(ans);
  }
} public class Main{
  public static void main(String args[]){
    Scanner sc = new Scanner(System.in);
    int a = sc.nextInt();
    int fh = a / 500;
    a = a - (fh * 500); 
    int f = a / 5;
    int ans = (fh * 1000) + (f * 5);
    System.out.println(ans);
  }
} Main
import java.util.Scanner;

public class Main{
  public static void main(String args[]){
    Scanner sc = new Scanner(System.in);
    int a = sc.nextInt();
    int fh = a / 500;
    a = a - (fh * 500); 
    int f = a / 5;
    int ans = (fh * 1000) + (f * 5);
    System.out.println(ans);
  }
}