import java.util.Scanner;

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