Memory

is a Console-based Unix-compatible Card Game.

To run the game

Go under the directory where the file memory.sh lives. Type ./memory.sh in your console, and press Enter!

How the game works

When the game begins, you will see a 4x4 grid of cards. (Total of 16 cards, 8 pairs) Your job is to flip the matching pairs until ALL cards have been flipped!

Instructions

Choose the pair of cards to flip by typing the number sequence in the order of Row1 Col1 Row2 Col2.
- Example: 1312 is Card 1 at (1, 3) and Card 2 at (1, 2)
Do the cards match?
- Yes: the cards will be flipped immediately.
- No: the values of the cards will be displayed for 2 seconds.
Once all cards have been flipped, you'll be redirected to the ending page where you have an option to play another.

To quit the game

Press ctrl+C or cmd+C anytime to exit.

Behind the Stage

Language: Shell script, because it's the most common language for console-based interactive games.

{FUNCTIONS}

initialize_board()

Call shuffle_letters() to fill in the board with pairs of random alphabets from {A...H}. Fill in another boolean matrix for indicating whether the card has been flipped or not.

print_matrix({opt: arg})

Prints either the card matrix or boolean matrix depending on the number of arguments.

0 argument = card matrix
1 or more arguments = boolean matrix The card matrix will hide or show the value of the card depending on the boolean value of the corresponding index of the boolean matrix. (The code for the print_matrix() function has been obtained from: https://stackoverflow.com/a/16487733)

shuffle_letters()

Input letters {A...H} in random orders in the left half of the card matrix. Shuffle the letters again in a different order and input into the other half of the card matrix.

display_board()

Essentially the main game page. Includes all components on what the screen of the game should include.

Composed of:

Current number of moves the user made
Newlines to make the UI prettier
The display of the card matrix

title_screen()

Short intro page of the game title and my name.

process_turn(row1, col1, row2, col2)

This function will only be called IFF the user enters a valid input, (so that invalid input doesn't count as a turn), increment the number of moves used by 1. Since the display_board() function only reveals the card value if its corresponding boolean value is True, set chosen two cards' boolean values to True. Reveal the board status. Reverse the board status to its previous form within 2 seconds if the cards are not matching. - During the 2 seconds of the board display, disable interrupt and prevent user input If a match is found, decrement the hidden pair count by 1 and return.

game_complete()

The ending page when the game is completed. I wanted to make the game rather generous and encourage completion than frustration (better UX), so there is no game over or time over.

Print:

Number of moves used
Short celebration message
Instruction for playing again If the user enters any character, prepare for a another game: (The input value for entering any character is programmed to be hidden from the user)
Reset hidden pair count to 8 and number of moves to 0.
Call start_game() function.

start_game()

Print the title screen by calling title_screen(). Get the cards ready by initializing through initialize_board(). Sleep for 0.7 seconds for the title screen display. Then call display_board() to display the cards to start the game!

the MAIN method

(Error handling) If an error occurs, redirect error file descriptor to /dev/null.

Call start_game() to start the game!

A while loop will be running which includes:

Several prompts to guide the user to input the ROW-COL values
Validate the input: Did user input numbers between 1~4?
- There are 4 different if statements for { Row-1 Col-1 Row-2 Col-2 }, to specifically indicate which input was invalid to the user.
Refresh the page by calling display_board()
Before the prompts for new inputs appear, output the warning messages:
- Invalid input for: { Row-1 Col-1 Row-2 Col-2 } (not numbers or out of bound)
- User has selected 2 of the same cards!
- User selected some cards that have already been flipped
If all passes, call process_turn()!

Final Thoughts

This game has been programmed to be efficient and deliver the best user experience. For example, starting a new game continues the while loop that has been running. All validation for user input is done within the while loop to prevent calling the process_turn() function with invalid inputs. User's number of moves only increment once valid input has been entered.

If I were to spend more time on this project in the future, I would like to create an interactive grid system where the user can highlight which card to flip instead of typing which row/col value of the card they would like to flip. Additinally, keeping the records of highest score, or lowest moves for the All-time high-score. As user plays each turn, saving previous inputs doesn't sound like a bad idea either.

This was a very unique and fun yet creative project that I had an opportunity to build. In the future, I hope to seek for opportunities where I can thoroughly enjoy exploring my own potentials.

Jieun Lee, 10/3/2019

jiena76/Memory