Description
1 Introduction
In this assignment, you will use two-dimensional array to implement a game called Gomoku (五子棋).
It is played on a game board. (We assume in this assignment.) Two players O and X
take turns to put their game discs into one unoccupied square of the board. The player who first
forms a line of five or more consecutive discs horizontally －, vertically ｜, or diagonally ＼／ wins
the game. (“Go” in Gomoku means “five” in Japanese.) The game is a draw when the board is full but
no player wins. Figure 1 shows an example configuration of Gomoku. The character ‘.’ denotes an
empty square. The rows and columns are named in numbers (0–12) and letters (A–M) respectively. If
Player X puts a disc to the square G7, then a diagonal line ／ of five consecutive X’s will be formed
and thus X will win.
A B C D E F G H I J K L M
0 . . . . . . . . . . . . .
1 . . . . . . . . . . . . .
2 . . . . . . . . . . . . .
3 . . . . . . . . . . . . .
4 . . . . . . . . . . . . .
5 . . . . . . . X X . . . .
6 . . . . . . . X O . . . .
7 . . . . . O . O O . . . .
8 . . . . . X X O O . . . .
9 . . . . X O O X X . . . .
10 . . . . . . . . . . . . .
11 . . . . . . . . . . . . .
12 . . . . . . . . . . . . .
Figure 1: An Example Game Configuration of Gomoku
2 Program Specification
2.1 Game Board
You can use a two-dimensional array of char to represent the game board.
const int N = 13;
…
char board[N][N];
The array elements board[0][0], board[0][12], board[12][0], and board[12][12] denote
the four corner squares A0, M0, A12, and M12 respectively.
2.2 Game Flow
1. The game starts with an empty game board. Player O takes the first turn.
2. In each move, you should prompt the player to enter two inputs denoting the square location
to be placed. You can assume that the first input is always a character and the second input is
always an integer.
A user input is invalid if: (a) it is not a proper cell location (i.e., rows 0–12 and columns A–M,
capital letters only), or (b) the input location is already occupied.
You should warn the player about invalid inputs and prompt the same player to enter again
until a valid input is entered.
3. Update the board by putting a disc to the appropriate square.
4. Determine if the current player has connected five or above.
5. Repeat Steps 2–4 until the game is finished. Alternate Players O and X in each round.
6. Once the game is finished, display the message “Player O wins!”, “Player X wins!”, or “Draw
game!” accordingly.
2.3 Other Notes
You are not allowed to use global variables in your program. (That is, you cannot declare any
variables outside any functions.) Nonetheless, const ones (e.g., N) do not count.
Your program should be decomposed into at least four functions (including main()). At least
two functions should have array parameter(s).
3 Program Output
The following shows some sample output of the program. The bold blue text is user input and the
other text is the program output. You can try the provided sample program for other input. Your
program output should be exactly the same as the sample program (i.e., same text, same symbols,
same letter case, same number of spaces, etc.). Otherwise, it will be considered as wrong, even if
you have computed the correct result.
A B C D E F G H I J K L M
0 . . . . . . . . . . . . .
1 . . . . . . . . . . . . .
2 . . . . . . . . . . . . .
3 . . . . . . . . . . . . .
4 . . . . . . . . . . . . .
5 . . . . . . . . . . . . .
6 . . . . . . . . . . . . .
7 . . . . . . . . . . . . .
8 . . . . . . . . . . . . .
9 . . . . . . . . . . . . .
10 . . . . . . . . . . . . .
11 . . . . . . . . . . . . .
12 . . . . . . . . . . . . .
Player O, make a move: G -1↵
Invalid input. Try again!
Player O, make a move: P 8↵
Invalid input. Try again!
Player O, make a move: E 6↵
A B C D E F G H I J K L M
0 . . . . . . . . . . . . .
1 . . . . . . . . . . . . .
2 . . . . . . . . . . . . .
3 . . . . . . . . . . . . .
4 . . . . . . . . . . . . .
5 . . . . . . . . . . . . .
6 . . . . O . . . . . . . .
7 . . . . . . . . . . . . .
8 . . . . . . . . . . . . .
9 . . . . . . . . . . . . .
10 . . . . . . . . . . . . .
11 . . . . . . . . . . . . .
12 . . . . . . . . . . . . .
Player X, make a move: C 11↵
A B C D E F G H I J K L M
0 . . . . . . . . . . . . .
1 . . . . . . . . . . . . .
2 . . . . . . . . . . . . .
3 . . . . . . . . . . . . .
4 . . . . . . . . . . . . .
5 . . . . . . . . . . . . .
6 . . . . O . . . . . . . .
7 . . . . . . . . . . . . .
8 . . . . . . . . . . . . .
9 . . . . . . . . . . . . .
10 . . . . . . . . . . . . .
11 . . X . . . . . . . . . .
12 . . . . . . . . . . . . .
Player O, make a move: C 11↵
Invalid input. Try again!
Player O, make a move: F 5↵
A B C D E F G H I J K L M
0 . . . . . . . . . . . . .
1 . . . . . . . . . . . . .
2 . . . . . . . . . . . . .
3 . . . . . . . . . . . . .
4 . . . . . . . . . . . . .
5 . . . . . O . . . . . . .
6 . . . . O . . . . . . . .
7 . . . . . . . . . . . . .
8 . . . . . . . . . . . . .
9 . . . . . . . . . . . . .
10 . . . . . . . . . . . . .
11 . . X . . . . . . . . . .
12 . . . . . . . . . . . . .
.
.
.
A B C D E F G H I J K L M
0 . . . . . . . . . . . . .
1 . . . . . . . . . . . . .
2 . X . . . . . . . . . . .
3 X . . . . . . O . . . . X
4 . . . . . . O . . . . . .
5 . . . . . O . . . . . . .
6 . . . . O . . . . . . . .
7 . . . . O . . . . . . . .
8 . . . . . . . . . . . . .
9 . . . . . . . . . . . . .
10 . . . . . . . . . . . . .
11 . . X . . . . . . . . . .
12 . . . . . . . X . . . . .
Player O, make a move: D 7↵
A B C D E F G H I J K L M
0 . . . . . . . . . . . . .
1 . . . . . . . . . . . . .
2 . X . . . . . . . . . . .
3 X . . . . . . O . . . . X
4 . . . . . . O . . . . . .
5 . . . . . O . . . . . . .
6 . . . . O . . . . . . . .
7 . . . O O . . . . . . . .
8 . . . . . . . . . . . . .
9 . . . . . . . . . . . . .
10 . . . . . . . . . . . . .
11 . . X . . . . . . . . . .
12 . . . . . . . X . . . . .
Player O wins!
4 Submission and Marking
Your program file name should be gomoku.cpp. Submit the file in Blackboard.
(https://elearn.cuhk.edu.hk/).
Insert your name, student ID, and e-mail address as comments at the top of your source file.
Besides the above information, your program should further include suitable comments as
documentation.
You can submit your assignment multiple times. Only the latest submission counts.
Your program should be free of compilation errors and warnings.
Plagiarism is strictly monitored and heavily punished if proven. Lending your work to others is
subjected to the same penalty as the copier.
(Many moves are skipped to save space. See Blackboard for full version.)
