import java.util.Scanner;

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

        Scanner sc = new Scanner(System.in);
        int n=sc.nextInt();
        int rem=n;
        int hap=0;
        int ans=0;
        if (n>=500){
            hap=n/500;
            ans=hap*1000;
            n=n-((n/500)*500);
        }
        if (n>=5){
            hap=n/5;
            ans=ans+hap*5;
        }
        System.out.println(ans);
    }
}

/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