import java.util.Scanner;

public class Main {
    public static void main(String args[]){

        Scanner sc = new Scanner(System.in);
        int X = sc.nextInt();
        int result = 0;

        result = result + (X/500)*1000;
        X = X -  (X/500)*500;
        result = result + (X/5)*5;

        System.out.println(result);

    }
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz