Concepts Of Programming Languages
12th Edition
ISBN: 9780134997186
Author: Sebesta, Robert W.
Publisher: Pearson,
expand_more
expand_more
format_list_bulleted
Expert Solution & Answer
Chapter 4, Problem 1RQ
Explanation of Solution
Syntax analyzers are based on grammars:
Syntax analyzer phase in compilation process is the step in which the “tokens” in the programs are identified and recognize whether they are specified in a valid way.
So, syntax analyzers are based on the syntax of the language. The syntax is often described formally by Context Free Grammars (CFG) or Backus-Naur Form (BNF).
Context Free Grammars (CFG):
There were four classes of grammars which describes the four classes of languages. Context Free Grammars was one of the four classes which described the syntax of whole
Backus-Naur Form (BNF):
BNF is a natural notation for describing syntax described by John Backus and Peter Naur. It is very similar to Context Free Grammars.
Thus, syntax is based on BNF (or context free grammar from) due to three main reasons as described below:
- Instead of using some informal notations, syntax description with context free grammars are precise and unambiguous. This is easy to understand for both human and software systems.
- The formal description of the syntax, CFG or BNF both are used as the direct basis of syntax analyzer.
- Context free grammars or BNF are easy to implement because of their modular nature. That is, they can be implemented in modules.
Want to see more full solutions like this?
Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!
Students have asked these similar questions
Change the following code so that there is always at least one way to get from the left corner to the top right, but the labyrinth is still randomized.
The player starts at the bottom left corner of the labyrinth. He has to get to the top right corner of the labyrinth as fast he can, avoiding a meeting with the evil dragon. Take care that the player and the dragon cannot start off on walls. Also the dragon starts off from a randomly chosen position
public class Labyrinth { private final int size; private final Cell[][] grid;
public Labyrinth(int size) { this.size = size; this.grid = new Cell[size][size]; generateLabyrinth(); }
private void generateLabyrinth() { Random rand = new Random(); for (int i = 0; i < size; i++) { for (int j = 0; j < size; j++) { // Randomly create walls and paths grid[i][j] = new Cell(rand.nextBoolean()); } } // Ensure start and end are…
Change the following code so that it checks the following 3 conditions:
1. there is no space between each cells (imgs)
2. even if it is resized, the components wouldn't disappear
3. The GameGUI JPanel takes all the JFrame space, so that there shouldn't be extra space appearing in the frame other than the game.
Main():
Labyrinth labyrinth = new Labyrinth(10);
Player player = new Player(9, 0); Dragon dragon = new Dragon(9, 9);
JFrame frame = new JFrame("Labyrinth Game"); GameGUI gui = new GameGUI(labyrinth, player, dragon);
frame.add(gui); frame.setSize(600, 600); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.setVisible(true);
public class GameGUI extends JPanel { private final Labyrinth labyrinth; private final Player player; private final Dragon dragon; //labyrinth, player, dragon are just public classes
private final ImageIcon playerIcon = new ImageIcon("data/images/player.png");…
Make the following game user friendly with GUI, with some simple graphics. The GUI should be in another seperate class, with some ImageIcon, and Game class should be added into the pane.
The following code works as this: The objective of the player is to escape from this labyrinth. The player starts at the bottom left corner of the labyrinth. He has to get to the top right corner of the labyrinth as fast he can, avoiding a meeting with the evil dragon. The player can move only in four directions: left, right, up or down. There are several escape paths in all labyrinths. The player’s character should be able to moved with the well known WASD keyboard buttons. If the dragon gets to a neighboring field of the player, then the player dies. Because it is dark in the labyrinth, the player can see only the neighboring fields at a distance of 3 units.
Cell Class:
public class Cell { private boolean isWall; public Cell(boolean isWall) { this.isWall = isWall; } public boolean isWall() { return…
Chapter 4 Solutions
Concepts Of Programming Languages
Ch. 4 - Prob. 1RQCh. 4 - Prob. 2RQCh. 4 - Prob. 3RQCh. 4 - Prob. 4RQCh. 4 - Prob. 5RQCh. 4 - Prob. 6RQCh. 4 - Prob. 7RQCh. 4 - Prob. 8RQCh. 4 - Prob. 9RQCh. 4 - Prob. 10RQ
Ch. 4 - Prob. 11RQCh. 4 - Prob. 12RQCh. 4 - Prob. 13RQCh. 4 - Prob. 14RQCh. 4 - Prob. 15RQCh. 4 - Prob. 16RQCh. 4 - Prob. 17RQCh. 4 - Prob. 18RQCh. 4 - Prob. 19RQCh. 4 - Prob. 20RQCh. 4 - Prob. 21RQCh. 4 - Prob. 22RQCh. 4 - Prob. 23RQCh. 4 - What was Knuths insight in developing the LR...Ch. 4 - Prob. 25RQCh. 4 - Prob. 26RQCh. 4 - Is left recursion a problem for LR parsers?Ch. 4 - Prob. 1PSCh. 4 - Prob. 2PSCh. 4 - Prob. 3PSCh. 4 - Prob. 4PSCh. 4 - Prob. 7PSCh. 4 - Prob. 8PS
Knowledge Booster
Similar questions
- Discuss the negative and positive impacts or information technology in the context of your society. Provide two references along with with your answerarrow_forwardA cylinder of diameter 10 cm rotates concentrically inside another hollow cylinder of inner diameter 10.1 cm. Both cylinders are 20 cm long and stand with their axis vertical. The annular space is filled with oil. If a torque of 100 kg cm is required to rotate the inner cylinder at 100 rpm, determine the viscosity of oil. Ans. μ= 29.82poisearrow_forwardMake the following game user friendly with GUI, with some simple graphics The following code works as this: The objective of the player is to escape from this labyrinth. The player starts at the bottom left corner of the labyrinth. He has to get to the top right corner of the labyrinth as fast he can, avoiding a meeting with the evil dragon. The player can move only in four directions: left, right, up or down. There are several escape paths in all labyrinths. The player’s character should be able to moved with the well known WASD keyboard buttons. If the dragon gets to a neighboring field of the player, then the player dies. Because it is dark in the labyrinth, the player can see only the neighboring fields at a distance of 3 units. Cell Class: public class Cell { private boolean isWall; public Cell(boolean isWall) { this.isWall = isWall; } public boolean isWall() { return isWall; } public void setWall(boolean isWall) { this.isWall = isWall; } @Override public String toString() {…arrow_forward
- Please original work What are four of the goals of information lifecycle management think they are most important to data warehousing, Why do you feel this way, how dashboards can be used in the process, and provide a real life example for each. Please cite in text references and add weblinksarrow_forwardThe following is code for a disc golf program written in C++: // player.h #ifndef PLAYER_H #define PLAYER_H #include <string> #include <iostream> class Player { private: std::string courses[20]; // Array of course names int scores[20]; // Array of scores int gameCount; // Number of games played public: Player(); // Constructor void CheckGame(int playerId, const std::string& courseName, int gameScore); void ReportPlayer(int playerId) const; }; #endif // PLAYER_H // player.cpp #include "player.h" #include <iomanip> Player::Player() : gameCount(0) {} void Player::CheckGame(int playerId, const std::string& courseName, int gameScore) { for (int i = 0; i < gameCount; ++i) { if (courses[i] == courseName) { // If course has been played, then check for minimum score if (gameScore < scores[i]) { scores[i] = gameScore; // Update to new minimum…arrow_forwardIn this assignment, you will implement a multi-threaded program (using C/C++) that will check for Prime Numbers and Palindrome Numbers in a range of numbers. Palindrome numbers are numbers that their decimal representation can be read from left to right and from right to left (e.g. 12321, 5995, 1234321). The program will create T worker threads to check for prime and palindrome numbers in the given range (T will be passed to the program with the Linux command line). Each of the threads works on a part of the numbers within the range. Your program should have some global shared variables: • numOfPrimes: which will track the total number of prime numbers found by all threads. numOfPalindroms: which will track the total number of palindrome numbers found by all threads. numOfPalindromic Primes: which will count the numbers that are BOTH prime and palindrome found by all threads. TotalNums: which will count all the processed numbers in the range. In addition, you need to have arrays…arrow_forward
- How do you distinguish between hardware and a software problem? Discuss theprocedure for troubleshooting any hardware or software problem. give one reference with your answer.arrow_forwardYou are asked to explain what a computer virus is and if it can affect computer’shardware or software. How do you protect your computer against virus? give one reference with your answer.arrow_forwardDistributed Systems: Consistency Models fer to page 45 for problems on data consistency. structions: Compare different consistency models (e.g., strong, eventual, causal) for distributed databases. Evaluate the trade-offs between availability and consistency in a given use case. Propose the most appropriate model for the scenario and explain your reasoning. Link: [https://drive.google.com/file/d/1wKSrun-GlxirS31Z9qoHazb9tC440AZF/view?usp=sharing]arrow_forward
- Operating Systems: Deadlock Detection fer to page 25 for problems on deadlock concepts. structions: • Given a system resource allocation graph, determine if a deadlock exists. If a deadlock exists, identify the processes and resources involved. Suggest strategies to prevent or resolve the deadlock and explain their trade-offs. Link: [https://drive.google.com/file/d/1wKSrun-GlxirS31Z9qoHazb9tC440 AZF/view?usp=sharing]arrow_forwardArtificial Intelligence: Heuristic Evaluation fer to page 55 for problems on Al search algorithms. tructions: Given a search problem, propose and evaluate a heuristic function. Compare its performance to other heuristics based on search cost and solution quality. Justify why the chosen heuristic is admissible and/or consistent. Link: [https://drive.google.com/file/d/1wKSrun-GlxirS31Z9qoHazb9tC440 AZF/view?usp=sharing]arrow_forwardRefer to page 75 for graph-related problems. Instructions: • Implement a greedy graph coloring algorithm for the given graph. • Demonstrate the steps to assign colors while minimizing the chromatic number. • Analyze the time complexity and limitations of the approach. Link [https://drive.google.com/file/d/1wKSrun-GlxirS3IZ9qoHazb9tC440 AZF/view?usp=sharing]arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Np Ms Office 365/Excel 2016 I NtermedComputer ScienceISBN:9781337508841Author:CareyPublisher:Cengage
Np Ms Office 365/Excel 2016 I Ntermed
Computer Science
ISBN:9781337508841
Author:Carey
Publisher:Cengage