EECE 230 Lab Classes, Fall 2012

EECE 230 INTRODUCTION TO PROGRAMMING Lab Assignment 8 1. Snakes-and-ladders is an ancient board game in which two or more players race to the finish tile using dice rolls. Every time a player reaches a snake tile, he/she is moved backward a number of tiles. On the other hand, reaching a ladder tile causes the player to advance several locations forward. In this exercise, you need to mimic a snakes-and-ladders game with one player and count the number of steps required to reach the finish tile. You can assume that there are 100 tiles and that each dice roll results in a random number between 1 and 6. Also, you can assume that snakes are found at tiles that are multiples of 13 and ladders are found at tiles with prime numbers (except 13). The number of steps to move forward (in case of ladders) or backwards (in case of snakes) is a random number between 1 and 10. To do this, you need to implement a class Game with the following members: • Private member currentLocation of type int • Default constructor that sets currentLocation to 0 • Member function bool isAtFinishTile() that returns true if the current location is 100 and false otherwise • Member function bool isAtLadderTile() that returns true if the current location is a ladder tile and false otherwise • Member function bool isAtSnakesTile() that returns true if the current location is a snake tile and false otherwise • Member function void rollDice() that generates a random number between 1 and 6 and updates currentLocation accordingly • Member functions void moveForward() and void moveBackward() that generate a random number between 1 and 10 and update currentLocation accordingly. Note that the value of currentLocation should never become less than 0 or greater than 100. Also, you need to write a main that instantiates an object of type Game and keeps rolling the dice until the player reaches the finish tile. Of course, every time the player reaches a ladder tile or a snake tile, the appropriate action must be done. The program must print the intermediate locations as well as the total number of steps taken to reach the finish tile. 2. In this exercise you are going to develop a simple system to manage a DVD rental store. a. Implement a class DVDType with the following members: • Private members: title (of type string), genre (of type string), and nbCopiesAvailable (of type int) • Default constructor that sets title and genre to “” and nbCopiesAvailable to 0 • Member functions: string getTitle(), string getGenre(), and int getNbCopiesAvailable() • Member function void set(string, string, int) that sets title, genre, and nbCopiesAvailable to the values specified as parameters • Member function void rentDVD() which decrements the number of copies available • Member function void returnDVD() which increments the number of copies available b. Write a program to manage the information related to the DVD store as follows: • Declare a named constant maxSize as a global variable to represent the max number of DVDs in the store and initialize it to 1000. Note that the number of DVDs might be much less than that. • Write a function void loadData(DVDType A[]) that reads the information about the DVDs from a file called “dvds.txt” and stores it in an array A whose size is equal to maxSize. If the number of DVDs is less than maxSize, then the remaining (rightmost) cells in A will be considered empty. Each line in the file contains information about one dvd using the following format title genre nbCopiesAvailable You can assume that the title and the genre contain no spaces. • Write a function void saveData(DVDType A[]) that stores the data of A in “dvds.txt” using the format described above. Note that you need to discard the empty cells. • Write a function int searchByTitle(string str, DVDType A[]) that returns the index of the DVD in A whose title is equal to str. It returns -1 if the DVD doesn’t exist • Write a function void displayByGenre(string str, DVDType A[]) that displays all DVDs in A whose genre is equal to str. • At the beginning of main, you need to declare an array of DVDType and read the information from “dvds.txt” using loadData. Then, you should repeatedly ask the manager to select one of the following functionalities: 1. Search by title: read a title from the manager and tell whether the corresponding DVD exists in the store 2. Display by genre: read a genre from the manager and display the titles of all DVDs of that genre 3. Rent DVD: read a title from the manager and decrement the number of copies of the corresponding DVD. If the title doesn’t exist or if there are no available copies, an error message should be generated. 4. Return DVD: read a title from the manager and increment the number of copies of the corresponding DVD. If the title doesn’t exist or if there are no available copies, an error message should be generated. 5. Exit: exit the loop. • After the main exits the loops and right before termination, the program should save the updated data in “dvds.txt” using saveData. 3. You are required to redo exercise 1 of assignment 4 using object oriented methodology. As such, you need to do the following: a. Implement class Point that has the following members: • Private variables x and y of type double that represent the coordinates of the point. • Default constructor that initializes x and y to random values between 0 and 1. • Setters and getters b. Implement class Circle with the following members: • Private variables x and y of type double that represent the coordinates of the center. • Private variable R of type double that represents the length of the radius. • Default constructor that initializes x and y to 0 and R to 1. • Function bool containsPoint(Point p) that return true if p lies inside the circle and false otherwise. c. Write a main that reads a positive integer N from the user and prints an estimate of π using N random points. That is, you have to create one instance of class Circle with center (0,0) and radius 1 and N instances of class Point. For each point you create, you check whether it lies inside the unit circle and update the counter accordingly. If M points lie inside the circle, then the estimate of π would be 4 � � �.