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