The homework due date has been extended because you need to turn in two distinct implementations:

1. one that uses CGI.pm (documentation from lecture notes nine)
2. another one that doesn't use CGI.pm

We'll talk about this in class on Thu, Feb 5.

Also, please make sure you

• read,
• understand, and
• comply with

the Computer Science Department's Statement on Academic Integrity before turning in your assignment.

You and the computer play a game.

• When the game starts the score is 0 (zero) for the computer, and 0 (zero) for you.
• The computer chooses FIRST (one of paper, rock, scissors) and
• (for debugging purposes) it shows that choice to you.
• You then get to choose and submit your choice.
• The computer checks its choice against yours.
• (paper beats rock, rock beats scissors, but scissors beats paper)
• and determines who gets the point (you or it).
• Then the new score is updated, listed, and the computer makes a new choice,
• sends it to you and you get to provide a new choice as well and thus keep the game going.

import java.io.*;
import java.util.*; 

class Two {
    public static void main(String[] args) throws IOException {
        BufferedReader b = 
            new BufferedReader(new InputStreamReader(System.in));
        String line; 
        int user, computer, pointsUser = 0, pointsComputer = 0; 
        String[] choices = { "rock", "scissors", "paper" }; 
        Hashtable h = new Hashtable(); 
        h.put("rock"   , new Integer(0)); 
        h.put("scissors", new Integer(1)); 
        h.put("paper"   , new Integer(2)); 
        Object choice; 
        System.out.println("Hello and welcome to the game.");           
        do {
            computer = (int)(Math.random() * choices.length); 
            System.out.println("*** The computer has chosen: (" + choices[computer]  + ")"); 
            System.out.println("Now it's your turn.");
            System.out.println("Paper, scissors, or rock...");
            System.out.print("Which will it be? Type here: ");
            line = b.readLine(); 
            choice = h.get(line); 
            String message = "*** The computer's choice was: " + choices[computer];
            if (choice == null) {
                System.out.println("Sorry, this is not a valid choice."); 
                System.out.println("The computer has just scored one on you.");
                System.out.println("Its choice was: " + choices[computer]);
                pointsComputer += 1;                 
            } else {
                user = ((Integer)choice).intValue();               
                if ((user + 1) % 3 == computer) {
                    System.out.println("Very good.\n" + message);
                    System.out.println("***(So, you win.)***"); 
                    pointsUser += 1; 
                } else if ((computer + 1) % 3 == user) {
                    System.out.println("Too bad.\n" + message);
                    System.out.println("***(So, you lose.)***"); 
                    pointsComputer += 1; 
                } else {
                    System.out.println(message + "\n***(This game's a draw.)***"); 
                }
                System.out.println("The score is now: "); 
                System.out.println("  Computer: " + pointsComputer); 
                System.out.println("  You     : " + pointsUser); 
            }            
        } while (true);   
    }
}

Here's a session with the program above:

frilled.cs.indiana.edu%javac Two.java
frilled.cs.indiana.edu%java Two
Hello and welcome to the game.
*** The computer has chosen: (rock)
Now it's your turn.
Paper, scissors, or rock...
Which will it be? Type here: scissors
Too bad.
*** The computer's choice was: rock
***(So, you lose.)***
The score is now: 
  Computer: 1
  You     : 0
*** The computer has chosen: (scissors)
Now it's your turn.
Paper, scissors, or rock...
Which will it be? Type here: paper
Too bad.
*** The computer's choice was: scissors
***(So, you lose.)***
The score is now: 
  Computer: 2
  You     : 0
*** The computer has chosen: (paper)
Now it's your turn.
Paper, scissors, or rock...
Which will it be? Type here: rock
Too bad.
*** The computer's choice was: paper
***(So, you lose.)***
The score is now: 
  Computer: 3
  You     : 0
*** The computer has chosen: (paper)
Now it's your turn.
Paper, scissors, or rock...
Which will it be? Type here: scissors
Very good.
*** The computer's choice was: paper
***(So, you win.)***
The score is now: 
  Computer: 3
  You     : 1
*** The computer has chosen: (rock)
Now it's your turn.
Paper, scissors, or rock...
Which will it be? Type here: rock
*** The computer's choice was: rock
***(This game's a draw.)***
The score is now: 
  Computer: 3
  You     : 1
*** The computer has chosen: (rock)
Now it's your turn.
Paper, scissors, or rock...
Which will it be? Type here: ^Cfrilled.cs.indiana.edu%