BA 371 VB.Net Assignment 1: Noughts & Crosses aka Tick-Tack-Toe

Program the game of Noughts and Crosses, aka Tick-Tack-Toe, the game played on a 3x3 board of squares where two players alternately claim a square by putting a nought or a cross in it. The player who gets three crosses or noughts in a row, either horizontally, vertically or diagonally, wins the game. In case all spaces are taken and there is no winner, the game results in a draw.

Please carefully read all the matarial on this page and pay careful attention to the requirements stated below.

Click here for a demo version of the program (note: this is a command-line/console application; not a windows/graphics program!)

Requirements

The program should exibit the following behavior and structure:

• Your program must run as a Console Application; i.e., do not!! implement it as a Windows Application.
• !!! The board must be held in memory as a 3x3 two-dimensional array of shorts!!! (see your VB.Net lab exercises for how to hold data in a two-dimensional array and for how to pass arrays to functions.
• Before each move, the board and the currently free and occupied fields must be displayed (see image above). This should be abstracted in a subroutine display_board(ByRef the_board(,) as Short). (Note that display_board() gets a two-dimensional array the_board passed in).
  

• A move is specified by typing the number 1 - 9 indicating the square to be occupied. Squares are numbered by row; i.e.,
  

  
    ------------- 
    | 1 | 2 | 3 | 
    ------------- 
    | 4 | 5 | 6 | 
    ------------- 
    | 7 | 8 | 9 | 
    ------------- 
      
  

  A move is only valid if the square is not occupied and if the typed number is larger than 0 and smaller than 10. In case of an invalid move, generate an error and prompt for a new move. Make sure that your program does not accept nonnumeric input.
• After each move, check to see if there is a winner using the function:

  check_for_winner(ByRef the_board(,) as Short) as Short

  that returns either a winner or no winner.

• The program does not have to play multiple rounfs of the game; a single game is all we ask for. However, a user should, of course, be able to run the program many times without ever running into an error.

• The program itself does not play! The program merely prompts for moves, keeps track of the board and diagnoses the validity and results of moves. For each move, the program prompts the player on turn.
• Player names are NOUGHTS and CROSSES.

Please Note!!

• You are expected to use some standard 'good programming' practices:

• Always have Option Strinct On and Option Explicit On set.

• Include sufficient commenting in your code so that others who are not familiar with your application can comfortably read your code and understand what it does. You will be asked to review each others' code; so you should make it legible and easily understandable.
  

• Use mnemonic variable names; i.e., use names that represent what they mean. For instance, if you have a counter of sorts, call it counter, rather than i or j.  (i and j for loop indexes are fine, however).

• Introduce a function/subroutine naming convention that makes it easy for people reading your code to distinguish between functions and subroutines that you wrote versus the ones that come supplied with VB.Net; e.g., start all your functions and subroutines with an underscore; e.g., _myFunction(). (There exists a sizable literature on naming conventions, name spaces, etc. We do not need to detail any of this here, but it makes sense to introduce at least a few, simple conventions that increase the readability of your code). Make sure that you include your naming conventions in a comment block (there is little point in having the convention if you don't tell your reader what it is!).

• Thoroughly check for errors and exceptions. Colleagues reviewing your code will be asked to try and 'break it.' Make sure they cannot.