import java.util.Scanner;
import java.util.Hashtable;
import java.util.Enumeration;
import java.util.StringTokenizer;
import java.util.ArrayList;
import java.util.Collections;
import java.io.FileInputStream;
import java.io.FileNotFoundException;

/** Driver.java for User Login lab.
 * This is the only file you need to modify.
 * The purpose is to practice with Java's built-in Hashtable class.
 * We'll read an input file that stores user login information for
 * a computer system.  Each line of the file contains a user's name
 * and an amount of time logged in.  See the file login.txt.  Read
 * the file, and create a Hashtable of users.  The keys will be the
 * user names, and the values will be the minutes of computer time
 * that the person was logged in.  
 * As you read in the data, you need to note if you have ever seen 
 * this person before.  If the person is already in the hash table,
 * then just update the value, otherwise insert a new name/minutes
 * pair into the hash table.  
 * When you're done, dump the contents of the hash table into an 
 * ArrayList and sort the users in descending order of login time.
 * Print the users' info, one person per line.
 */
public class Driver
{
  public static void main(String [] args) throws FileNotFoundException
  {
    // This declaration says that the keys are Strings (i.e. names)
    // and the values are integers (total minutes of login time).
    Hashtable<String, Integer> table = new Hashtable<String, Integer>();

    Scanner in = new Scanner(new FileInputStream("login.txt"));

    while(in.hasNextLine())
    {
      // Part 1:  Input
      // The first 8 characters on the line are the user name.
      // The amount of login time is given as hh:mm inside parentheses.
      //   We can tokenize on () and look for the 2nd token.
      //   From hh and mm we can compute the number of minutes
      //   for this login session.
      
      
      
      
      // Part 2:  Insert/update information in Hashtable.
      // Have we seen this user before?  If so, just update time.
      if (false)
      {


      }
      
      // Otherwise, we need to put this user name and time into
      // the Hashtable for the first time.
      else
      {


      }
    }

    // Part 3:  Now we are done reading the file and initializing the 
    // hash table.  Time to sort and output.
    // A "User" is someone who has a username and number of login minutes.
    // Create an ArrayList of User objects.
    // Use the technique we did in the Hash2 example of food to
    // "enumerate" the keys of the table, in order to dump each (key,value)
    // pair into the array list.
    
    
    
    
    
    // Use the Java API and UserComparator class to sort the list,
    // and then print it out.
    // The names in the output should be left justified, and the numbers
    // should be right justified.



  }
}