OS_L1_1

import java.io.File;
import java.io.FilenameFilter;
import java.util.Scanner;

public class HW01_1 {
    public static void main(String args[]){
        String path;
        Scanner s=new Scanner(System.in);
        path=s.nextLine();
        System.out.println(path);
        File f;
        s.close();
        try{
            f=new File(path);
            File [] files=f.listFiles(new FileFilter());
            double size=0;
            for(File q :files){
                size+=q.length();
            }
            if(files.length!=0)
            System.out.printf("%.2f bytes",size/files.length);
            else
                System.out.println("0");
        }
        catch (Exception e){
            System.exit(-1);
        }
    }
}
class FileFilter implements FilenameFilter{
    @Override
    public boolean accept(File dir, String name) {
        name=name.substring(name.length()-4,name.length());
        if(name.equals(".txt"))
            return true;
        return false;
    }

}