UMBC, CMSC202 Computer Science II, Spring 2007

Project 1: Hockey Ratings

Due: Sunday, February 25, 2007, 11:59pm + 59 seconds

Objective

Background

Assignment

Project 0: Due Friday, February 16, 2007

As stated in the course project policy, Project 0 is a required part of the course. You must complete the following tasks by midnight Friday, February 16.

1. Copy to your own directory the following file in the GL file system: /afs/umbc.edu/users/c/h/chang/pub/cs202/proj0/secrets

2. Add a comment of your own choosing to the bottom of the file using a text editor of your choice.

3. Submit the modified file to Project 0: submit cs202 proj0 secrets

Project 1: Due Sunday, February 25, 2007

You are given the header files of two C++ classes: Stat and Player: stat.h, player.h. You must work with these files as given and not change them in anyway. The Stat class is mostly a data class --- there is an overloaded < operator to allow for comparisons. The Stat class has just two data members: game and pmRating. The game member holds the game number of a particular game. The pmRating member holds the plus-minus rating of a player in that game.

The Player class is more complicated. Since Player has dynamically allocated data members, several member functions have been implemented already, including the default constructor, the destructor and the assignment operator. (You will find out more about these later this semester). The implementations of these functions are in player.cpp.

Player contains a vector of Stat records --- one for each game that the player has played in. The medianRating member contains the median plus-minus rating of the player in the games he/she played in.

Part 1 of your assignment is to implement the following 3 member functions in Player:

• void AddStat(Stat& s) ;

  This member function should add s to the record vector and update medianRating.

• void Print() const ;

  This member function should print out the name and medianRating fields.

• void PrintAll() const ;

  This member function should print out the name and medianRating fields as well as the plus-minus rating for each game played.

Another member function called debug() exists to allow you to have access to private data members for debugging purposes. You should not use debug() in your final submission.

Part 2 of your assignment is to write a main program that reads in the data for each player. For this project, we will use UNIX input redirection to supply the input to the program. So, your program should read from the standard input. Each player's record must then be inserted into a priority queue, where the priority is determined by the player's median plus-minus rating.

The priority queue data structure will maintain its items so that the item with the highest priority is at the "top". If the top item is popped off (i.e., removed), the priority queue adjusts itself so that the item with the next highest priority is on top. You will be using the priority queue class from the Standard Template Library (STL). Details are below.

The main program must then remove the top 5 players from the priority queue and print out their statistics using PrintAll(). Finally, the program removes the rest of the players from the priority queue (in medianRating order) and prints out their names and median rating using Print().

Part 3 of your project is to create an input file that thoroughly tests your program. Although your program does not have to deal with improperly formatted input, you must still check that your program works with "weird" but properly formatted input. Both sample input files given to you are relatively nice. It is your responsibility as the programmer to construct these "weird" test cases. Your grade for this part of the project depends the "weirdness" of the input file you construct.

Implementation Notes

• You should follow the CMSC202 Coding Standards.

• When there are an even number of items, we will define the median to be the higher of the two "middle" numbers. For example, the median of (1, 3, 8, 9, 11, 24) is 9 (and is not 8.5).

• You should not modify the file player.cpp that has the code for the Player member functions that are already implemented for you. Put your code for the Player member functions in a file called myplayer.cpp.

• The input for your program is in a convenient format. A player's data starts with a line consisting of the player's name followed by white space and the number of games played. The player's name does not have any white space. In the lines that follow a player's name, each line has two numbers, a game number followed by the player's plus-minus rating for that game.

  Two sample input files have been provided to you: input1.txt, input2.txt.

  Sample output for input1.txt is also provided: output1.txt.

• To use the UNIX input/output redirection (assuming your executable file is called a.out): ./a.out <input1.txt >output1.txt

• The method cin.eof() returns true when the end of file has been reached.

• There is an alternate constructor that assigns a player's name.

• STL priority queues are discussed only briefly in your textbook (p. 845). The C/C++ Reference Site has a listing of the methods available in a priority queue. In short you need to #include <queue> and use the definition: priority_queue<Player> Q ; After that, the push(), pop(), size(), top() and empty() methods will be available. Note that the return type of pop() is void

• The project files linked in this web page are also available on the GL file system, in the directory: /afs/umbc.edu/users/c/h/chang/pub/cs202/proj1/ You can copy these files to your own directory using the UNIX command: cp /afs/umbc.edu/users/c/h/chang/pub/cs202/proj1/* .

Hints:

• There is a discussion of explicit constructor calls on page 279 of your textbook.

• Recall that you can declare local variables inside statement blocks marked by { and }. When execution exits the block, the variables go "out of scope".

Grading

• Projects will be graded on five criteria: correctness, design, style, documentation and efficiency. So, turning in a project that merely "works" is not sufficient to receive full credit.

• If you did not look over the Academic Conduct Policy for this course, do so now! Note that both the copier and the "copy-ee" are penalized. If you do not understand something about the policy, ask for clarification. Ignorance is not an acceptable excuse.

• Remember that the late policy is a 25% penalty for submissions up to 24 hours late. Projects more than 1 day late will receive zero.

Turning in your program

1. myplayer.cpp must contain the implementation of the remaining member functions in player.h
2. proj1.cpp must contain the main function that completes Part 2 of the project.
3. myinput.txt must be a test input file that you created to show that you have fully exercised your program.
4. myoutput.txt must be the output of your program given myinput.txt.

Do not submit any of the files that were given to you: stat.h, player.h and player.cpp. Since you are not allowed to change these files, your program should compile and run correctly with the original versions of these files.

When you are done, use the class name 'cs202' and the project name 'proj1' to submit your project. The UNIX command to do this should look like: