Assignment 2 - Tic Tac Toe + -Lab 3 Exercises

Introduction In this assignment, you will implement programs that play Tic Tac Toe. Unlike Lab Exercise 3 where the computer managed a board for two human players entering their move as input, with this assignment a human player would be able to play against the computer. Assignment SpecificationIn Lab Exercise 3, you were asked to build a class Tic-Tac-Toe with the following public interface: drawBoard() Prints the current state of the Tict-Tac-Toe board boardFull() Returns True is the board is full and False otherwise cellIsEmpty(cell) Returns True if the cell is available, False otherwise assignMove(cell,ch) Assigns the character ch to the cell of the board. whoWon() Returns the symbol of the player who won if there is a winner, otherwise it returns an empty string Extend the solution of Lab Exercise 3 and write a python program to allow the user to play Tic-Tac-Toe against the computer. Your new program should include the possibility to have two human players against each other, but also the possibility to play against the computer with three different strategies: a sequential strategy, a the Relation to Lab Exercises This assignment is related to Lab exercise 3. You could and should use the same class as the one used for the lab exercise. A solution for Lab Exercise 3 has been posted on-line. Check the folder Lab 3 Material. random strategy and a clever strategy. Your program should present a menu to the user to chose the type of game such as: Welcome to Tic Tac Toe Series User against user ...............1 User against dumb computer ......2 User against random computer ....3 User against smart computer......4 Quit ............................5 Enter your choice The program should detect when a player won or when there is a draw, and should validate the input. Validation includes checking whether a cell is already filled when selected as well as bounding the index between 1 and 9. At the end of the game, the computer should return to the menu after announcing the winner. At the start of a game the computer should give the user the choice of symbol and the "x" is the one that starts. Do you want to play x or o? All input should be validated. The three game strategies to implement are as follows: Strategy: Dumb Computer The computer selects sequentially from 1 to 9 the first available cell and places its symbol. Strategy: Random Computer The computer selects randomly from the available cells and places its symbol. Strategy: Smart Computer The computer first checks if it can win in the next move. If so, it places its symbol to complete the line. If there is no winning position, the computer checks whether the opponent could win in the next move. If so, the computer blocks it by placing its symbol. Otherwise, the computer checks if the centre is free and takes the centre since it is part of 4 different possible lines. If the centre is not available, the computer checks the availability of corners, since each corner is part of three different possible lines, and places its symbol on one random available corner. Finally, if nothing else is available, the computer places its symbol on a randomly selected available side. Assignment Deliverables You are going to submit one Python program that performs all the specified tasks. Submission Instructions Please follow these instructions to correctly submit your solution. Name your solution assignment2.py Submit your assignment2.py at the end of this page Note that late submissions w ill n o t b e a c c e p t e d .



-Lab 3 Exercises The exercises are about building the game of Tic Tac Toe. Tic Tac Toe is a game for two players who take turns to fill a 3 X 3 grid with either o or x. Each player alternates choosing an open space in the grid to mark with either x for a player or o for the other player. The goal (to win) is to have three xs or 3 os in a row, column or diagonal. The game can also end with a draw if the grid is full but no line is formed. The exercises combined will allow us to implementing Tic Tac Toe for two human players to play it on a computer. 1. Write a program that displays the Tic Tac Toe board. We have a python class in the provided file Lab3Exercise.py that initializes a board with a list of empty characters. class TicTacToe: def __init__(self): # "board" is a list of 10 strings representing the board (ignore index 0) self.board = [" "]*10 self.board[0]="#" The constructor __init__ creates a list of 10 one character strings. The first one at index 0 will be ignored (initialized with some character but not space) and the other 9 represent the 9 cells of the Tic Tac Toe grid. Write the method assignMove(self, cell,ch) that requests the Tic Tac Toe object to assign the symbol/letter ch to the position cell of the grid. The argument ch is assumed to be either “x” or “o”. However, cell is a number and should be between 1 and 9. Write the method drawBoard(self) that would display the board as follows: x | x | o 7 | 8 | 9 ----------- ----------- o | o | x 4 | 5 | 6 ----------- ----------- x | o | x 1 | 2 | 3 The first grid on the left represents the current state of the board while the grid on the right is static, and represents the index of each cell (like the numeric pad on the keyboard). The two grids are separated by a tab (\t). Once you wrote your methods, create an object Tic Tac Toe with myBoard=TicTacToe() fill some cells in the board using for example myBoard.assignMove(4,”x”) to put an x in the 4th cell, then display the board. If the list board of the instance TicTacToe contains [“#”, “x”,”o”,”x”,”o”,”o”,”x”,”x”,”x”,”o”], the board should look as above. If the list contains [“#”, “o”,”o”,”o”,”x”,”x”,”x”,”x”,”x”,”o”] the board should look like: x | x | o 7 | 8 | 9 ----------- ----------- x | x | x 4 | 5 | 6 ----------- ----------- o | o | o 1 | 2 | 3 If the list contains [“#”, “o”,”o”,”o”,”o”,” ”,”o”,”o”,”o”,”o”] the board should look like: o | o | o 7 | 8 | 9 ----------- ----------- o | | o 4 | 5 | 6 ----------- ----------- o | o | o 1 | 2 | 3 Write the methods boardFull(self) to check if the board is full, and cellIsEmpty(self, cell) to check whether a given cell is available. Make sure the argument cell is correct and will not generate an error of out of bound. If it is out of bound, the method should return False. Write a small program to use and test these methods. 2. Continue the class TicTacToe by completing the method isWinner(self, ch) which returns True if the symbol in ch forms either a horizontal line, a vertical line or a diagonal line, and False otherwise. A line is formed by three consecutive cells with the same symbol (as in ch). This method is called within the method whoWon(self) provided in the python file. Write a small program that uses and test these methods to fill the cells with assignMove check whether the board is full, whether a given cell is available, who won and display the board. 3. Write a program that allows two players, x and o, to alternate and provide their moves on the board. For instance asking the question: It is the turn for x . What is your move? The program should check the input and only allow a valid cell between 1 and 9. Also, a cell that is not available (already filled) should not be allowed as a new move. The program should iterate until the game is over and display who won or whether there is a draw. Here are some examples of output at the end of a game. x | x | o 7 | 8 | 9 ----------- ----------- o | o | x 4 | 5 | 6 ----------- ----------- x | o | x 1 | 2 | 3 It's a tie. x | o | o 7 | 8 | 9 ----------- ----------- x | x | o 4 | 5 | 6 ----------- ----------- | | x 1 | 2 | 3 x wins. Congrats!