SLR(1) Praser 1

Duration: 5 min

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Inside: a video lesson and guided study material.

Module outline

  1. HPSC Interview Preparation: Interview Preparation
  2. Python Language: Introduction to Python, Tokens, Variables, Data Types, I/O, Operators & Expressions, Control Flow & Looping, Collections & Strings, Functions & Modules, File Handling & Data Analysis, DSA using Python
  3. Data Structure & Algorithms: Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing, Algorithm Analysis, Sorting Algorithms, Minimum Spanning Trees, Time Complexity Analysis, Graph Theory, Shortest Path Algos
  4. Computer Networks: Introduction to CN, Data Communication, DLL: Access Control, DLL: Flow Control, Data Link Layer - Ethernet, Net Layer: IPv4 & Proto, Net Layer: IP Addressing, Transport Layer Services, TL: Congestion & UDP, Application Layer, Hardware basics, Network Security
  5. Computer System & Organisation: Basics of COA, Cache Memory Organization, Input Output Organisation, Pipelining, Instr Formats & Modes, Control Unit Design, Programming the Basic Computer
  6. 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, Transaction Management, Concurrency Control
  7. Operating Systems: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Deadlock, Threads & Process Creation, Memory Management, Virtual Memory, Disc Scheduling
  8. Digital Logic & Circuits: Digital Systems & Boolean Basics, Logic Gates & Hardware, Boolean Expression, Boolean Minimization, Combinational Circuit, Sequential Circuits, Number System, Number Representation
  9. Theory Of Computation: Introduction to TOC, Deterministic FA (DFA), Non-Deterministic FA, Regular Expressions, Grammar, Regular Language Properties, Pushdown Automata & CFG, Turing Machines, Moore & Mealy Machines
  10. Compiler Design: Intro to Compilers, Lexical Analysis, Grammar & CFG, Syntax Analysis: Top-Down, Syntax Analysis: Bottom-Up, Semantic Analysis & SDT, Intermediate Code Gen, Code Optimization, Run Time Environment
  11. Software Engineering: Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management, Data Warehousing & Mining
  12. Introduction to Emerging Trends: Emerging Tech Trends
  13. Digital Society & Cyber Law: Society, Law & Ethics
  14. HPSC PGT Previous Year Paper:
  15. HPSC Assistant Professor Previous Year Paper:
  16. Live Sessions: HPSC Live Sessions, EMRS TGT/PGT Live Class
  17. Full Mock Test:
  18. HPSC PGT - MOCK Test Series:
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

The video provides a detailed lecture on SLR(1) parsing, a method used in compiler construction. It begins by defining the procedure for constructing an SLR(1) parse table, highlighting its similarities and differences with LR(0) parsing. The core distinction lies in the handling of reducing entries, which are restricted by the Follow sets of non-terminals. The lecture then transitions to a practical example, demonstrating the step-by-step construction of a parse table for a specific grammar, illustrating how to identify and resolve conflicts to determine if a grammar is SLR(1).

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The instructor presents a slide titled 'SLR(1)' outlining the procedure for constructing the parse table. He notes that while the procedure is similar to LR(0), there is a specific restriction on reducing entries. He underlines the term 'LR(0)' to emphasize the comparison. He explains that whenever a final item exists in a state, the reduce entries are placed under the Follow symbol of the Left-Hand Side (LHS) symbol. He writes this rule clearly on the slide. He concludes this section by defining an SLR(1) grammar as one where the parse table is free from multiple entries (conflicts). He emphasizes that if multiple entries exist, the grammar is not SLR(1). He also mentions that the restriction applies specifically to reducing entries, distinguishing it from shift entries which follow standard LR(0) logic.

  2. 2:00 – 4:43 02:00-04:43

    The scene shifts to a whiteboard example with the grammar A -> aA / b. The instructor displays a DFA with states I0 through I4 and a corresponding parse table. He demonstrates filling the table, specifically focusing on state I3 which contains the final item A -> b.. He explains that the reduce action r2 (for A -> b) should be placed in the columns corresponding to the Follow set of A. He writes r2 in the table for state I3. He discusses the implications of these entries and how they relate to the grammar's structure, ensuring the table remains conflict-free for an SLR(1) grammar. He points to the table and the DFA states to connect the theoretical rules with the practical construction. He also writes down the grammar rules A' -> A, A -> aA, A -> b to clarify the production numbers used in the table.

This lecture segment effectively bridges the gap between theoretical definitions and practical application in compiler design. By first establishing the strict rules for SLR(1) table construction—specifically the use of Follow sets to resolve reduce entries—the instructor provides a clear framework. The subsequent example with the grammar A -> aA / b serves to solidify these concepts, showing exactly how final items in DFA states translate to reduce actions in the parse table. This progression from abstract rules to concrete table filling helps students understand how to identify SLR(1) grammars and avoid parsing conflicts. The visual aids, including the DFA diagram and the parse table, are crucial for visualizing the state transitions and action placements.

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