import java.util.*;

public class Main {

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

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

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

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int x = sc.nextInt();
        sc.close();
        int a = x / 500;
        int b = (x % 500) / 5;
        int res = a*1000 + b*5;
        
        System.out.println(res);
    }
} Main
import java.util.*;

public class Main {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int x = sc.nextInt();
        sc.close();
        int a = x / 500;
        int b = (x % 500) / 5;
        int res = a*1000 + b*5;
        
        System.out.println(res);
    }
}