CSCI3180 – Principles of Programming Languages – Spring 2019Assignment 3 — Perl and Dynamic ScopingDeadline: Apr 7, 2019 (Sunday) 23:591 IntroductionThe purpose of this assignment is to offer you the first experience with Perl, which supports bothdynamic and static scoping. Our main focus is on dynamic scoping.The assignment consists of two parts. First, you need to implement a game called “Maze Race”in Perl with dynamic scoping. Then, you are required to re-implement this task using Python withstatic scoping. The detailed object-oriented design for the Perl implementation is given, and you areasked to design a similar framework in the Python realization. In the process, you will experienceboth the programming flexibility and readability with dynamic scoping. Your implementation inPerl should be able to run with Perl v5.14.2. Besides, you are required to add “use warnings;” atthe start of your program. For the Python part, Python 3.6 is demanded. Good coding styles areexpected.IMPORTANT: All your codes will be graded on the Linux machines in the Department.You are welcome to write your codes on your own machines, but please test them on the givenDepartments machines (the perl version in linux1 is 5.14.2) before your submission.NO PLAGIARISM! You are free to devise and implement the algorithms for the given tasks,but you must not “steal/copy” codes from your classmates/friends. If you use some code snippetsfrom public sources or your classmates/friends, ensure you cite them in the comments of your code.Failure to comply will be considered as plagiarism.2 Task: Maze RaceIn this task, you need to implement a maze race game with Perl. Note that dynamic scoping isbeneficial and required here, and you need to explain why your implementation using dynamicscoping (specifically, with the local keyword in Perl) is more convenient.With dynamic scoping, you can 1) implicitly affect the behavior of functions in function callingsequences without passing extra parameters, and 2) temporarily mask out some existing variables.Full marks on this task demands you to show both of these two properties with your code andexplanations.You should strictly follow our OO design in you implementation. You have to follow theprototypes of the given classes exactly. You can choose to add new member variables and functionsif necessary.2.1 The StoryIn ancient Greece, there was a mysterious creature called Minotaur, with a bull-like head and tail,and a humanoid body. The surrounding villagers had been suffering from the monster’s bullyingfor a long time. Barely a man could match Minotaur’s mighty power and agility, let along killing it.To seek peaceful living, Greek people came up with a temporary solution to isolate the monster.The architect Daedalus and his son Icarus designed and built the Labyrinth (a Greek term formaze). Then they seduced Minotaur to dwell at the center of the Labyrinth to prevent it fromengaging with humans. But still, nobody could deliver death to Minotaur even it was trapped inthe building. Years later, the mighty Greek hero Theseus rose and took the mission of terminatingMinotaur. He received the blueprint of the Labyrinth from Daedalus and found a feasible path tokill Minotaur.Thousands years after the battle between Theseus and Minotaur, rumors are spread acrossthe world that Theseus left some treasures in that Labyrinth. You, a promising and gifted Greekexplorer, make up your mind to retrieve these precious items for your homeland. Meanwhile, aheritage smuggling company employs a treasure hunter to loot for Theseus’s legacy. So please becool and quick, draw your strategies now.12.2 Task DescriptionYou are required to realize a treasure hunting game that involves two players: Player 1 and Player2. Both players are located in a different entrance of a maze respectively. The maze is organizedinto a 2-dimensional array of cells, which can be empty or occupied by a solid wall, a player, orthe treasure. Besides, they both know where the treasure is but initially know nothing about themaze itself except their own locations and the dimensions of the maze (height and width). Theinitial positions of the two players are of the same Manhattan distance to the treasure. Normally,a player can attempt to move one step to an adjacent empty cell in the north (N), south (S), east(E), and west (W) directions. A player cannot move out of the maze. A wall always block a move,except when a special move is employed. Initially, all cells are unknown, except those containingthe two players and the treasure. As a player attempts to move to the next cell, the new cell willbe revealed to all players.This game is turned-based, meaning the two players make move alternately. Player 1 movesfirst. The player who reaches the treasure first will win this game. Note that reaching the treasuremeans the player has just moved into the cell containing the treasure.Figure 1: The neighborhood of Player 1 using move. The green cell is feasible while red cells areblocked. Best viewed on screen.Players move in the maze alternately. In addition to a normal move, a player can make threemore special moves: rush, walk through a blocked cell, and teleport. A move enables a player to move from his/her current location to a neighboring (the 4 compassdirection: N, W, S, E, like where the arrows point to in Figure 1) and feasible/available(empty or only containing the treasure) cell. If the neighboring cell of the current playeris a wall or occupied by the other player, then the current player remains in the samecell after attempting the move. The detailed logic of move is given in the skeleton code(maze_race_components.pm) within class Player. Players can rush through a clean (no obstacles) vertical or horizontal path until right beforean edge of the maze, or a cell that is occupied by a wall or player. Check out Figure 2 forillustrations. All cells along the path of a rush will be revealed.2Figure 2: The neighborhood of Player 1 using rush. The green cells are feasible while red cell isblocked. Best viewed on screen. If a player is next to a wall or the other player. This player can choose to walk through theblocked cell (by the wall/player) to the next empty cell. This special move cannot go throughmore than one level of blocked cell though. On the other hand, if there is no wall/player infront of the player, then walk through a blocked cell degenerates to a normal move.Figure 3: The neighborhood of Player 1 using walk through a blocked cell. The green cells arefeasible while red cell is blocked. Best viewed on screen. Influenced by the magic in the maze, players have a choice to be teleported to a random cellwithin the maze. If the target cell is feasible then this teleportation succeeds. Otherwise, thisteleportation fails and the player remains in the original cell, but the target cell is revealedon the map.Note Each player can only make special moves at most four times. Moreover, failed moveattempts would not change players’ locations, but they would reveal the cell contents (feasible or3not) on the map if that cell has not been explored yet.Hint Implement special moves via dynamic scoping.The basic logic of the game is presented in “maze race.pl”, which has been provided to you.Please check the file for more details.2.3 Perl ClassesPlease follow the classes MazeRace, Player, Maze, Cell, and Position defined below in your Perlimplementation. You are free to add other variables, methods or classes, but cannot modify/deleteours. Please stick to our naming convention and getter/setter style too. We would start theprogram by running: perl maze_race.pl.1. Class MazeRaceThis class realizes a simple game board for hosting the competition between two players.You have to implement it with the following components: Instance Variable(s)maze- A maze instance of class Maze defined below, maintaining maze related information.In the following specification, all variables named as maze have the same meaningas here unless otherwise specified.player1- A player instance of class Player (defined below) standing for player 1.player2- A player instance of class Player (defined below) standing for player 2. Instance Method(s)new(file)- Instantiate an object of Class MazeRace, initialize its maze and players’ information(the name of player 1 is ‘E’ and the name of player 2 is ‘H’) from file, and return thisobject. file is a string storing the path of the test file. In the following specification,all variables named as file have the same meaning as here unless otherwise specified.start()- Start the maze race.2. Class PlayerA class representing a player in the game. You have to implement it with the followingcomponents: Instance Variable(s)name- The name of the player.curPos- The current position of the player. It is an instance of class Position.specialMovesLeft- How many move times that the current player can make a special move (no matterwhether this move fails or succeeds). It should be initialized to 4.rshift- A one-dimensional array describing the offsets related to this position in row tostand for a normal move to the S, E, N and W directions, e.g. our $rshift = (1, 0, -1,0);cshift4- A one-dimensional array describing the offsets related to this position in columnto stand for a normal move to the S, E, N and W directions, e.g. our $cshift = (0, 1, 0,-1); Instance Method(s)new(name)- Instantiate an object of Class Player with its name, and return this object.setName(name)- The setter of this player’s name.getName()- The getter of this player’s name.getPos()- The getter of this player’s position. It returns an object of class Position.occupy(maze)- Update the cell content as the player moves into the current location in the maze.leave(maze)- Update the cell content as the player leaves the current location in the maze.move(pointTo, maze)- The player moves to a new location (one step away) according to the given directionindicated by pointTo in that maze. If he/she is blocked on the way, he/she wouldremain still. In our game setting, pointTo is an integer from 0 to 3 indicating thecompass direction (0: south, 1: east, 2: north, 3: west). In the following specification, allvariables named as pointTo have the same meaning as here unless otherwise specified.next(pointTo)- Return the position of the neighbor of the player in the direction pointTo.rush(pointTo, maze)- The player rushes to a new location based on the given direction (pointTo) inthat maze. The player would stop at where he/she is hindered on the way.throughBlocked(pointTo, maze)- The player can walk through one blocked cell when he/she is facing a wall or theother player and the cell behind the wall/player is available.teleport(maze)- The player will be teleported to a random cell in the maze. Note that the targetcell could be in any position of the maze, including this player’s current location, otherplayer’s location, infeasible cells blocked by walls, available cells, and the location of thetreasure.makeMove()- Make the current player move to a position based on the instruction of the humanuser. The interaction can be invoked by standard I/O.3. Class MazeA class representing a maze in the game. You have to implement it with the followingcomponents: Instance Variable(s)map- A two-dimensional array of object of class Cell recording maze information. Initially,all cells are not explored.height- The height of the maze.width5- The width of the maze.destPos- The position of the destination (where we can find the treasure). It is an instanceof class Position. Instance Method(s)new()- Instantiate an object of Class Maze, initialize its instance variables, and returnthis object.getHeight()- The getter of the height of the maze.getWidth()- The getter of the width of the maze.getCell(pos)- The getter of the cell of the maze in the given position (pos). pos is an instanceof class Position. In the following specification, all variables named as pos have thesame meaning as here unless otherwise specified.setCell(pos, cell)- The setter of the cell of the maze in the given position (pos). cell is an instanceof class Cell.getCellContent(pos)- The getter of the cell content of the maze in the given position (pos).setCellContent(pos, value)- The setter of the cell content of the maze in the given position (pos).isAvailable(pos)- Check whether the cell in the given position (pos) is feasible or not. It will returna -1/0/1 value (-1: infeasible, 0: out of range, 1: feasible).explore(pos)- Mark the cell at the given position (pos) as explored.reachDest(pos)- Return whether we can find the treasures in the given position (pos) as a 0/1value (0: not found, 1: found).Figure 4: A visual example about the maze information.displayMaze()- Print the maze information to a standard output device (screen). Specifically,players are represented by the initials of their names (like ‘E’ and ‘H’ by default), and6the treasure is denoted by ‘O’. For known cells, ‘ ’ (one blank) denotes empty cell and‘#’ denotes wall. For unknown cells, they are all shown as ‘?’. An example is given inFigure 4.loadMaze(file)- Load the maze related information from a given file (to be explained in furtherdetails).4. Class CellA class representing a cell in the maze. You have to implement it with the following components: Instance Variable(s)pos- The position of this cell. Here pos is an instance of class Position defined below.content- A character representing the content of this cell. ‘#’ denotes wall, and ‘*’ denotesan empty cell, ‘E’ denotes Player 1, ‘H’ denotes Player 2, and ‘O’ denotes the treasure.explored- A 0/1 value indicating whether this cell is explored (1) or not (0). Instance Method(s)new()- Instantiate an object of Class Cell, initialize its instance variables, and returnthis object.setExplored(value)- The setter of the variable explored.getExplored()- The getter of the variable explored.setPos(pos)- The setter of the variable pos which is an object of class Position.getPos()- The getter of the variable pos.setContent(value)- The setter of the variable content.getContent()- The getter of the variable content.isAvailable()- Return whether this cell is available (1) or not (0) as a 0/1 value.5. Class PositionA class representing a position in the maze. You have to implement it with the followingcomponents: Instance Variable(s)r- The row number of this position.c- The column number of this position.7 Instance Method(s)new()- Instantiate an object of Class Player, initialize its instance variables, and returnthis object.getC()- The getter of the column number c.getR()- The getter of the row number r.setC(value)- The setter of the column number c.setR(value)- The setter of the row number r.2.4 Execution ContextWe provide you with the skeleton code in “maze race.pl” and “maze race components.pm”. Youare not allowed to change our code, but can only insert your own code. Your implementationshould be able to run with the main program in “maze race.pl”.Figure 5: The input of Player 1.2.5 Input/Output SpecificationAll possible mazes with the positions of the treasures and two players are given in the specificationfile. The data format is given below. InputH W#1###2#8Figure 6: Check the input for Player 2 and request the input again if that is invalid.****#**##*###*#******#*#O##*The first line gives the height (H, where 2 ≤ H ≤ 70) and width (W, where 2 ≤ W ≤ 70) ofthe maze. The remaining H lines give the maze information. The detailed maze description isgiven in a 2D matrix form, where ‘#’ denotes wall and ‘*’ denotes an empty cell, ‘O’ denotestreasure, ‘1’ and ‘2’ denote players 1 and 2 respectively. Note ‘O’, ‘1’ and ‘2’ only show uponce in the maze information.Note each line in the given test file is ended with ‘ ’. Once again, we use ‘*’ to denote anempty cell in the input file while ‘ ’ (a blank) is used to show an empty cell on the screen(Figure 4).You can assume the input file to be error free.How to control a Player’s Move Players require user-inputs to determine their nextmoves. When it is one player’s turn during the game, your program should request for thetype and direction of the next move. The input should be integers from 0 to 2 for the typeand from 0 to 3 for the direction. When inputting the moving type, hitting ENTER directlywithout giving any number will control the current player to make a normal move.If the target cell is available, the player will move to that cell. If not, the information of thetarget cell will be uncovered. An example is presented in Figure 5. After this, the systemswitches to the other player’s turn automatically.Moreover, any invalid input should be forbidden and the user is requested for input again untila valid move is given. See Figure 6. Note we will also display the number of remaining specialmoves that a player can make in each turn. When a player runs out of all his special moves,9Figure 7: Player 2 used up all his/her special moves, and he/she is defaulted to make a normalmove from now on.this player needs no more user-input for choosing the moving type (the moving direction stillrequires interaction) as shown in Figure 7.If you choose 3 (teleport), then there is no need for direction input.Your implementation should output exactly the same message as shown in the examples inthe figures.? OutputFigures 8 and 9 show partial output during the game. Specifically, at the beginning of thegame, only the locations of Player 1 and 2 and the treasures are visible, and the remainingcells are invisible, denoted by ‘?’. No matter whether the movement of a player succeeds orfails, the information (replacing ‘?’ with ‘#’, ‘ ’, ‘E’, or ‘H’) of the target cell will be revealedpermanently.When a player reaches the treasure first, the game will output the information like Figure10 and then end.Note all the input and output statements are provided to you in the skeleton code. Do notmodify them in any way.2.6 Grading CriteriaYour program should run by calling ‘perl maze race.pl’ and will be tested. You will also beevaluated on your implementation of the given classes (with dynamic scoping when necessary) andprogramming style.3 Implementing Maze Race via PythonIn this task, you are asked to implement Maze Race using Python with exactly the same classdesign. You should adopt and adapt to the class design and skeleton code in Section 2 for thistask. Also, the input/output specifications and grading criteria are the same as those in theprevious task. All your implementations are required to be written into a single Python file namedas “maze race.py”.10Figure 8: The partial output of the game state in one turn. The turn of Player 1.Figure 9: The partial output of the game state in one turn. The turn of Player 2.11Figure 10: Player 2 wins the game.4 ReportYour report should explain the following questions within TWO A4 pages. Provide example code and necessary elaborations for demonstrating the advantages of DynamicScoping in using Perl to implement Maze Race as compared to the correspondingcodes in Python. Discuss the keyword local in Perl (e.g. its origin, its role in Perl, and real practical applicationsof it) and giving your own opinions.5 Submission GuidelinesPlease read the guidelines CAREFULLY. If you fail to meet the deadline because of submissionproblem on your side, marks will still be deducted. So please start your work early!1. Your submissions will be accepted the latest by 11:59 p.m. on Apr 7, but submissions madeafter the original deadline would be considered as LATE submissions and penalties will beimposed in the following manner:12? Late submissions before 11:59 p.m. on Apr 8: marks will be deducted by 20%.? Late submissions before 11:59 p.m. on Apr 9: marks will be deducted by 50%.2. In the following, SUPPOSEyour name is Chan Tai Man,your student ID is 1155234567,your username is tmchan, andyour email address is tmchan@cse.cuhk.edu.hk.3. In your source files, insert the following header. REMEMBER to insert the header accordingto the comment rule of Perl./ CSCI3180 Principles of Programming Languages --- Declaration --- I declare that the assignment here submitted is original except for source material explicitly acknowledged. I also acknowledge that I am aware of University policy and regulations on honesty in academic work, and of the disciplinary guidelines and procedures applicable to breaches of such policy and regulations, as contained in the website http://www.cuhk.edu.hk/policy/academichonesty/ Assignment 3 Name : Chan Tai Man Student ID : 1155234567 Email Addr : tmchan@cse.cuhk.edu.hk/The sample file header is available athttp://course.cse.cuhk.edu.hk/~csci3180/resource/header.txt4. Late submission policy: less 20% for 1 day late and less 50% for 2 days late. We shall notaccept submissions more than 2 days after the deadline.5. The report should be submitted to VeriGuide, which will generate a submission receipt. Thereport should be named “report.pdf”. The VeriGuide receipt of the report should be named“receipt.pdf”. The report and receipt should be submitted together with codes in the sameZIP archive.6. Tar your source files to username.tarJust tar all your source files, report.pdf, and receipt.pdf for Assignment 3.tar tmchan.tar cvf maze race.pl maze race components.pm maze race.py report.pdfreceipt.pdf7. Gzip the tarred file to username.tar.gz bygzip tmchan.tar8. Uuencode the gzipped file and send it to the course account with the email title “HW3studentID yourName” byuuencode tmchan.tar.gz tmchan.tar.gz | mailx -s HW3 1155234567 Chan Tai Man csci3180@cse.cuhk.edu.hk9. Please submit your assignment using your Unix accounts.1310. An acknowledgment email will be sent to you if your assignment is received. DO NOTdelete or modify the acknowledgment email. You should contact your TAs for help if you donot receive the acknowledgment email within 5 minutes after your submission. DO NOTre-submit just because you do not receive the acknowledgment email.11. You can check your submission status athttp://course.cse.cuhk.edu.hk/~csci3180/submit/hw3.html.12. You can re-submit your assignment, but we will only grade the latest submission.13. Enjoy your work :>14本团队核心人员组成主要包括硅谷工程师、BAT一线工程师，精通德英语！我们主要业务范围是代做编程大作业、课程设计等等。我们的方向领域：window编程 数值算法 AI人工智能 金融统计 计量分析 大数据 网络编程 WEB编程 通讯编程 游戏编程多媒体linux 外挂编程 程序API图像处理 嵌入式/单片机 数据库编程 控制台 进程与线程 网络安全 汇编语言 硬件编程 软件设计 工程标准规等。其中代写编程、代写程序、代写留学生程序作业语言或工具包括但不限于以下范围:C/C++/C#代写Java代写IT代写Python代写辅导编程作业Matlab代写Haskell代写Processing代写Linux环境搭建Rust代写Data Structure Assginment 数据结构代写MIPS代写Machine Learning 作业 代写Oracle/SQL/PostgreSQL/Pig 数据库代写/代做/辅导Web开发、网站开发、网站作业ASP.NET网站开发Finance Insurace Statistics统计、回归、迭代Prolog代写Computer Computational method代做因为专业，所以值得信赖。如有需要，请加QQ：99515681 或邮箱：99515681@qq.com 微信：codehelp
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