Spring Semester 2002

In this lab you will implement a game.

The game works as follows:

1. When the game starts the computer chooses a secret number.

   The number is chosen randomly between the values of 1 and 100 (inclusive).

2. The user then proceeds to guess the number.

3. Every time the user enters a number the computer provides an answer.

4. If the guess is smaller than the number, the computer reports it.

5. If the guess is bigger than the number, the computer reports it.

6. If the guess is equal to the number the computer reports.

7. Each guess is tallied into a variable, count.

8. If the user guesses the number before or with the 10^th guess, the user wins.

9. If the count becomes 10 and the user still hasn't guessed the number, the user looses.

You are to provide three implementations:

• one in CGI with Perl

• one in PHP (without using sessions)

• one in PHP (using sessions)

Before you start programming, design your program.

Here's a flow chart to get you started.

Here (also) is an implementation to get an idea.

burrowww.cs.indiana.edu% cat number
#!/usr/bin/perl

print "Hi there, are you ready?\n"; 

$x = 1 + int(rand(100)); # this is the number

print "I have chosen a number (between 1 and 100). \n"; 

$count = 0; 

print "You need to guess it in at most 10 tries.\n"; 

while (true) {

  $count += 1; 
  print "Guess", $count, "> "; 
  $guess = <STDIN>; 
  
  if ($guess < $x) { print "Try higher.\n"; }
  elsif ($guess > $x) { print "Try lower.\n"; }
  else { print "Congratulations!"; 
    print "You guessed in $count attempts.\n"; 
    exit; 
  } 

  if ($count == 10) { 
    print "You just ran out of attempts.\n"; 
    print "You lost. Better luck next time. Good-bye!\n"; 
    exit; 
  } 

}
burrowww.cs.indiana.edu% 

Here's a session with the program:

burrowww.cs.indiana.edu% ./number
Hi there, are you ready?
I have chosen a number (between 1 and 100). 
You need to guess it in at most 10 tries.
Guess1> 50
Try lower.
Guess2> 25
Try higher.
Guess3> 27
Try higher.
Guess4> 36
Try lower.
Guess5> 30
Try lower.
Guess6> 28
Try higher.
Guess7> 29
Congratulations!You guessed in 7 attempts.
burrowww.cs.indiana.edu% 

You are to:

• write a CGI script
• a PHP script (without sessions) and
• another PHP script (that uses sessions)

that implements the behaviour described above.

This will make a good review for the upcoming exam.

To review PHP, use the following links:

• Lecture Notes Eleven

• Lecture Notes Twelve

Good luck and let me know if we can be of any help!