Python Py Pac Poe Group Lab

Getting Started

First, your team will create a file inside a folder locally on a teammate's machine and push to Github, the rest of the team will fork and clone a copy.

Py Pac Poe User Stories

As a player (AAP), I want to see a welcome message at the start:

----------------------
Let's play Py-Pac-Poe!
----------------------

AAP, before being prompted for a move, I want to see the board printed out in the console, so that I know what moves have been made:
```
    A   B   C

1)  X |   | O
   -----------
2)    | X |
   -----------
3)  X | O | O
```

AAP, I want to be prompted with which player's move it is.

AAP, I want to be prompted on how to enter a valid move so that I don't make mistakes:

    A   B   C

1)  X |   | O
   -----------
2)    | X |
   -----------
3)  X | O | O

Player X's Move (example B2):

AAP, I want to be able to enter my move's column letter in upper or lower case (a/A, b/B or c/C) to make it easier to enter my move.

AAP, if I enter a move in an invalid format, or if I try to occupy a cell already taken, I want to see a message chastising me and be re-prompted:

Player X's Move (example B2): Z9
Bogus move! Try again...

Player X's Move (example B2):

AAP, at the end of a game I want to see who won the game:

Player X wins the game!

or if it was a tie

Another tie!

Hints

You can access, but not assign to global variables from within a function because it actually creates a new local variable instead (this is a downside of not have keywords like let in the language).

There's a couple of solutions. One is use the global statement as follows:

# Global variables
board = {}
turn = 'X'

# Will not work
def init_game():
	# Will not work because this creates a new variable
	# instead of assigning to the global board variable
	board = {
	'a1': None, `b1`: None, 'c1' None,
	# etc
	}
	turn = 'X'

# Do it like this
def init_game():
	# Use the global keyword to update global variables
	global board, turn
	board = {
	'a1': None, `b1`: None, 'c1' None,
	# etc
	}
	turn = 'X'

Using global is easy and works, however, it could be frowned upon by purists.

Another approach would be to use a global dictionary named something like state, which could then be mutated (updated) without a problem:

	# Global variables
	state = {}

	# The following works
	def init_game():
	  state['board'] = {
	  	'a1': None, `b1`: None, 'c1' None,
	  	# etc
	  }
	  state['turn'] = 'X'

Think through the game play of Tic-Tac-Toe and, if necessary, pseudocode it.
Think about how/where looping makes sense, e.g., loop until the player enters a correct move, until the game's over, etc.
Write several small functions, each performing a single purpose, e.g., init_game, print_board, get_move, get_winner, etc.
Modeling the board itself as a dictionary and naming the keys appropriately, can simplify updating the board based upon what the player types in. For example, assume you store the player's input in a variable named move, you can convert it to lower case using .lower(), and use it as the key to access the board, i.e., board[move].
The in operator is a great way to check if the player has entered a valid coordinate (a1, b1, etc.).

Bonus User Stories

AAP, I want to be prompted for a number of wins to play to before playing the first game.
AAP, I want to see the score after each game has ended:

SCORE:
Player X: xx   Player O: xx   Ties: xx

AAP, I want to see a congratulatory message when either player achieves the entered number of wins to play to:

Congrats to player X for winning 2 games!