import java.util.*;

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

/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