import java.util.*;
public class Main{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        int x = sc.nextInt();
        int cnt =0;
        
        cnt += (x/500)*1000;
        x = x-(x/500)*500;

        cnt+= (x/5)*5;
        System.out.println(cnt);
    }
} import java.util.*; util.* java public class Main{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        int x = sc.nextInt();
        int cnt =0;
        
        cnt += (x/500)*1000;
        x = x-(x/500)*500;

        cnt+= (x/5)*5;
        System.out.println(cnt);
    }
} Main public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        int x = sc.nextInt();
        int cnt =0;
        
        cnt += (x/500)*1000;
        x = x-(x/500)*500;

        cnt+= (x/5)*5;
        System.out.println(cnt);
    } main {
        Scanner sc = new Scanner(System.in);
        int x = sc.nextInt();
        int cnt =0;
        
        cnt += (x/500)*1000;
        x = x-(x/500)*500;

        cnt+= (x/5)*5;
        System.out.println(cnt);
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int x = sc.nextInt(); x sc.nextInt() sc.nextInt sc int cnt =0; cnt 0 cnt += (x/500)*1000 cnt (x/500)*1000 (x/500) x 500 1000 x = x-(x/500)*500 x x-(x/500)*500 x (x/500)*500 (x/500) x 500 500 cnt+= (x/5)*5 cnt (x/5)*5 (x/5) x 5 5 System.out.println(cnt) System.out.println System.out System System.out cnt String[] args args public class Main{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        int x = sc.nextInt();
        int cnt =0;
        
        cnt += (x/500)*1000;
        x = x-(x/500)*500;

        cnt+= (x/5)*5;
        System.out.println(cnt);
    }
} public class Main{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        int x = sc.nextInt();
        int cnt =0;
        
        cnt += (x/500)*1000;
        x = x-(x/500)*500;

        cnt+= (x/5)*5;
        System.out.println(cnt);
    }
} Main
import java.util.*;
public class Main{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        int x = sc.nextInt();
        int cnt =0;
        
        cnt += (x/500)*1000;
        x = x-(x/500)*500;

        cnt+= (x/5)*5;
        System.out.println(cnt);
    }
}
