Practice Question

Duration: 4 min

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Module outline

  1. Discrete Mathematics: Permutation, Combination and Probability / क्रमचय, संचय एवं प्रायिकता, Set Theory, Relations, Functions, Propositional and Predicate Logic, Graph Theory, Group Theory
  2. Digital Logic: Digital Systems & Boolean Basics, Boolean Expression, Boolean Minimization, Logic Gates & Hardware, Combinational Circuit, Sequential Circuits, Number System, Number Representation, Floating Point Rep
  3. Computer Organization and Architecture: Basics of COA, Programming the Basic Computer, Cache Memory Organization, Input Output Organisation, Instr Formats & Modes, Register Transfer and Microoperations, Control Unit Design, Pipelining, Multiprocessors
  4. Programming: Language Design, C Fundamentals, Control Flow, Functions, Arrays & Pointers, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling, OOPS with C++
  5. Data Structures: Introduction to DS, Array, Linked List, Stack, Queue, Tree, Graphs, Hashing
  6. Algorithms: Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms, Greedy Algorithms, Dynamic Programming, Minimum Spanning Trees, Shortest Path Algos, Advanced Algorithms
  7. Theory of Computation: Grammar, Regular Language Properties, Moore & Mealy Machines, Turing Machines
  8. 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, Introduction to TOC, Deterministic FA (DFA), Non-Deterministic FA, Regular Expressions, Pushdown Automata & CFG, Complexity Theory
  9. Operating Systems: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Threads & Process Creation, Deadlock, Memory Management, Virtual Memory, Disc Scheduling, File Management, Unix OS, Linux OS, Security
  10. Database Management Systems: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, File Organization & Indexing, Relational Algebra, SQL, Relational Calculus, Transaction Management, Concurrency Control, ORDBMS, NoSQL
  11. Computer Networks: Introduction to CN, Data Communication, DLL: Access Control, DLL: Flow Control, DLL: Error Control, DLL: Framing, Data Link Layer - Ethernet, Net Layer: IPv4 & Proto, Net Layer: IP Addressing, Net Layer:Routing Protocol, Transport Layer Services, TL: Congestion & UDP, Application Layer, Hardware basics, Network Security
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

The lecture focuses on converting a non-deterministic context-free grammar into a deterministic one using the left factoring technique. The problem statement presents the grammar S -> aAb / aABc / aABcd / aA / a. The instructor explains that this grammar is non-deterministic because multiple productions begin with the terminal 'a', creating ambiguity for a predictive parser. He systematically applies left factoring to resolve this. The process involves identifying common prefixes, extracting them into new non-terminals, and repeating the process until no common prefixes remain among the alternatives of any non-terminal. The final output is a set of productions where each rule starts with a unique terminal, ensuring determinism.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The instructor begins by analyzing the initial grammar S -> aAb / aABc / aABcd / aA / a. He identifies 'a' as the common prefix for all productions. He rewrites the rule as S -> aS'. The alternatives for S' are derived by removing the 'a': Ab, ABc, ABcd, A, and epsilon (representing the original a production). He then observes that Ab, ABc, ABcd, and A all start with the non-terminal 'A'. He factors out 'A' to create S' -> AS'' / epsilon. Next, he looks at S'' alternatives: b, Bc, Bcd, epsilon. He identifies 'B' as a common prefix for Bc and Bcd, rewriting S'' as S'' -> BS''' / b / epsilon. This window establishes the hierarchical structure of the factored grammar.

  2. 2:00 – 3:33 02:00-03:33

    The instructor finalizes the grammar by factoring the remaining alternatives for S'''. The current alternatives are c and cd. He identifies 'c' as the common prefix and introduces a new non-terminal S''''. He writes S''' -> cS''''. The new non-terminal S'''' handles the suffixes: epsilon (for the c case) and d (for the cd case), written as S'''' -> epsilon / d. He then organizes the final grammar by numbering the productions: 1. S -> aS', 2. S' -> AS'' / epsilon, 3. S'' -> BS''' / b / epsilon, 4. S''' -> cS'''', 5. S'''' -> epsilon / d. He reviews these steps to ensure the grammar is now deterministic and free of left recursion or common prefixes.

The video effectively demonstrates the iterative nature of left factoring. By breaking down the grammar into layers of non-terminals (S', S'', S''', S''''), the instructor removes ambiguity at each level. The final grammar is suitable for LL(1) parsing because the FIRST sets of the alternatives for each non-terminal are disjoint. This transformation is a fundamental step in compiler design for constructing efficient parsers.

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