CLR(1) Praser Part-1

Duration: 11 min

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Inside: a video lesson and guided study material.

Module outline

  1. About the Course: About the Course
  2. Section 1 | Language (Hindi): भाषा, लिपि, ध्वनि, वर्ण, अक्षर, स्वर, व्यंजन, मात्रा और संयुक्ताक्षर, वर्तनी, वर्ण-विन्यास, अनुस्वार, अनुनासिक, चंद्रबिंदु और ‘र’ के रूप, शब्द, पद और शब्द-भेद, संज्ञा और सर्वनाम, विशेषण और क्रिया, लिंग, वचन, पुरुष और कारक, काल, वाच्य, वाक्य और वाक्य-भेद, संधि, समास, विलोम शब्द, पर्यायवाची शब्द, सामान्य अशुद्धियाँ, अनेक शब्दों के लिए एक शब्द, मुहावरे और लोकोक्तियाँ, अपठित गद्यांश और अपठित पद्यांश, Multi-Topic Content (Cross-Concept Material), वर्णमाला
  3. Section 1 | Language (उर्दू भाषा — 22 प्रश्न (निश्चित)): Spelling & Diacritics, Grammar (اسم, فعل, صفت, ضمیر), Vocabulary, Idioms & Proverbs, Comprehension
  4. Section 1 | Language (বাংলা / बांग्ला भाषा — 22 प्रश्न (निश्चित)): Bangla Script and Sounds, Bangla Grammar and Usage, Bangla Word Formation and Vocabulary, Reading and Text Interpretation
  5. Section 1 | Language (English): Vocabulary, Noun, Subject Verb Agreement (Verb Noun Agreement), Adjectives, Tenses, Pronoun, Verb, Adverb, Preposition, Articles, Determiner, Conjunction, Modals, Active Passive Voice (Voice), Direct and Indirect Speech, Sentence Correction (Error Correction), Sentence Completion (Fill in the blanks), Sentence Construction, Sentence Re-arrangements (Para Jumbles) (Narrative Sequencing), Comprehension / Reading Comprehension / Unseen Passages (Critical Reasoning) (Paragraph Questions), Cloze Test (Cloze Passage), Verbal Analogy (Word Based Analogy), Facts, Inference and Judgements
  6. Section 2 | Primary Maths & Reasoning: Ratio and Proportion (Ratios), Divisibility Rules, Mixture and Alligation, Permutation and Combination, Number System, HCF LCM, Sequence and Series (Series), Speed Time and Distance, Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Percentage, Average, Profit and Loss, Simple Interest and Compound Interest, Time and Work, Mensuration and Geometry, Age Problems, Arithmetic, Powers and Exponents (Surds and Indices), Algebra, Probability, Trigonometry, Syllogisms, Seating Arrangements, Blood Relations, Directions (Direction Test), Analytical Reasoning (Counting Figures Reasoning), Puzzle Solving (Puzzles), Calendar, Clock, Cubes & Dices, Venn Diagram, Data Arrangement, Inequality, Analogy, Ranking, Order and Sequence
  7. Section 2 | General Awareness (GK + Current Affairs): Polity, Physics, Biology, State Wise GK, Chemistry, History, Geography, Indian Economy, Environment, GK- Current Affairs, Static General Knowledge
  8. Section 3 | Computer System and Org. (CSO): Basics of COA, Floating Point Rep, Cache Memory Organization, Instr Formats & Modes, Programming the Basic Computer, Input Output Organisation, Register Transfer and Microoperations, Control Unit Design
  9. Section 3 | Database Management System: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, SQL, File Organization & Indexing, Relational Algebra, Relational Calculus, Transaction Management, Concurrency Control
  10. Section 3 | Operating System: Introduction to OS, Process Management, CPU Scheduling, Threads & Process Creation, Memory Management, Virtual Memory, Disc Scheduling, File Management, Process Synchronization
  11. Section 3 | Computer Networks: Introduction to CN, Data Communication, DLL: Access Control, DLL: Flow Control, DLL: Error Control, Data Link Layer - Ethernet, Net Layer: IPv4 & Proto, Net Layer: IP Addressing, Transport Layer Services, TL: Congestion & UDP, Application Layer, Hardware basics
  12. Section 3 | Data Structures: Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing, Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms, Greedy Algorithms, Minimum Spanning Trees, Shortest Path Algos
  13. Section 3 | Theory Of Computation & Compiler Design: Introduction to TOC, Deterministic FA (DFA), Non-Deterministic FA, Regular Expressions, Grammar, Regular Language Properties, Moore & Mealy Machines, Pushdown Automata & CFG, Turing Machines, Intro to Compilers, Lexical Analysis, Grammar & CFG, Syntax Analysis: Top-Down, Syntax Analysis: Bottom-Up, Semantic Analysis & SDT, Intermediate Code Gen, Code Optimization
  14. Section 3 | Emerging Trends (AI, Societal Ethics & MS Office): Artificial Intelligence, Emerging Tech Trends, Society, Law & Ethics, MS Office Applications
  15. Section 3 | Software Engineering: Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Design, Estimation and Metrics, Software Maintenance and Configuration Management, Software Testing
  16. Section 3 | C Programming: C Fundamentals, Control Flow, Functions, Arrays & Pointers, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling
  17. Section 3 | OOPS, C++, JAVA, HTML: OOPS with C++, Java, HTML Basics, CSS
  18. Section 3 | Java: Java Fundamentals, Array, String, IO & References
  19. Section 3 | Python: Introduction to Python, Tokens, Variables, Data Types, I/O, Operators & Expressions, Control Flow & Looping, Collections & Strings, Functions & Modules, File Handling & Data Analysis
  20. Section 3 | Digital Electronics: Digital Systems & Boolean Basics, Logic Gates & Hardware, Boolean Expression, Boolean Minimization, Combinational Circuit, Sequential Circuits, Number System, Number Representation
  21. Section 3 | Multimedia: Multimedia
  22. BPSC Previous Year Papers:
  23. BPSC Full Mock Tests:
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

The video is an academic lecture on constructing a Canonical LR(1) Parsing Table for a given Context-Free Grammar. The instructor, Sanchit Jain, begins by presenting the grammar rules: S -> CC, C -> cC, and C -> d. He systematically demonstrates the process of grammar augmentation, closure computation, and the GOTO function to generate parser states. The lecture covers the derivation of the initial state I0, including the calculation of lookahead symbols, and proceeds to build subsequent states (I1 through I9) based on transitions. The session concludes with a complete state transition diagram that visualizes the shift, reduce, and accept actions required for the parser.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The instructor introduces the grammar rules S -> CC, C -> cC, C -> d. He begins the LR(1) construction by augmenting the grammar with S' -> S. He writes the initial state I0, showing items like S' -> .S, $ and S -> .CC, $. He explains the computation of lookahead symbols, specifically deriving {c, d} for the non-terminal C in the production S -> CC, resulting in items like C -> .cC, c/d. He emphasizes that the lookahead for the first C is determined by First(C$), which includes c and d because C can derive strings starting with c or d. He writes these items clearly on the whiteboard to establish the foundation for the parser states.

  2. 2:00 – 5:00 02:00-05:00

    The instructor proceeds to find transitions from the initial state I0. He identifies a transition on 'S' leading to state I1 (S' -> S., $), which is an accept state. He then identifies a transition on 'C' leading to state I2. In state I2, he writes the items S -> C.C, $, C -> .cC, $, and C -> .d, $. He explains that the lookahead for the second C is '$' because it follows the first C in the production S -> CC. He then identifies transitions from I2 on terminals 'c' and 'd', setting up the next states in the parser construction. He writes the items for I2 clearly on the board, showing the dot after the first C, indicating that the first C has been recognized.

  3. 5:00 – 10:00 05:00-10:00

    The instructor continues building the state diagram. He derives state I3 from I2 on input 'c', containing items C -> c.C, $ and closures C -> .cC, c/d, C -> .d, c/d. He identifies transitions from I3 on 'C', 'c', and 'd', leading to states I5, I6, and I7 respectively. He marks state I4 (from I2 on 'd') as a reduce state for C -> d. He similarly marks I5 and I7 as reduce states. He derives state I6 from I3 on 'c' and state I8 from I6 on 'C'. He also draws a transition from I2 on 'C' leading to state I9, which contains S -> CC., $ and C -> cC., $. The board becomes filled with a complex graph of states and transitions, illustrating the full Canonical LR(1) parsing table structure. He draws arrows for transitions like I3 -> C -> I5 and I6 -> C -> I8, and notes the reduce actions with specific lookaheads. He explicitly writes the items for each state, such as C -> cC., c/d in I5.

  4. 10:00 – 10:33 10:00-10:33

    The instructor concludes the lecture by reviewing the completed state transition diagram. He points to the various states (I0 through I9) and the arrows connecting them, emphasizing the structure of the Canonical LR(1) parser. He summarizes the final configuration of the parser states, ensuring all shift and reduce actions are accounted for in the diagram. He gestures towards the final graph to reinforce the connections between states, providing a visual summary of the entire parsing process. He ensures the audience understands the flow from the start state to the accept state, highlighting the final state I1.

The video provides a comprehensive walkthrough of Canonical LR(1) parsing table construction. Starting from a simple grammar, the instructor methodically applies the closure and GOTO operations to generate a complete set of parser states. The lecture highlights the importance of lookahead symbols in distinguishing between shift and reduce actions, a key feature of LR(1) parsing. The final state diagram serves as a visual representation of the parser's logic, connecting the theoretical concepts of grammar augmentation and item sets to a practical parsing mechanism.

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