Practice Question

Duration: 4 min

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Module outline

  1. Quantitative Aptitude: Ratio and Proportion (Ratios), Data Interpretation, Mixture and Alligation, Permutation and Combination, Number System, Sequence and Series (Series), Speed Time and Distance, Speed Mathematics and Basic Mathematics, Algebra, Percentage, Profit and Loss, Simple Interest and Compound Interest, Powers and Exponents (Surds and Indices), Time and Work, Mensuration and Geometry, Partnership
  2. Reasoning Ability: Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Data Sufficiency, Seating Arrangements, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Directions (Direction Test), Ranking, Order and Sequence, Syllogisms, Blood Relations, Puzzle Solving (Puzzles), Inequality, Machine Input-Output
  3. English Language: Vocabulary, Noun, Subject Verb Agreement (Verb Noun Agreement), Adjectives, Tenses, Comprehension / Reading Comprehension / Unseen Passages (Critical Reasoning) (Paragraph Questions), Cloze Test (Cloze Passage), Sentence Correction (Error Correction), Sentence Completion (Fill in the blanks), Sentence Re-arrangements (Para Jumbles) (Narrative Sequencing), Sentence Construction, Pronoun, Preposition, Conjunction, Adverb, Verb, Modals, Articles, Determiner, Interjection
  4. General Awareness: Evolution of Indian Banking (Banking & Financial Awareness), GK- Current Affairs, Static General Knowledge, Indian Economy
  5. C Concepts + MCQs (IT Specialist): C Programming by Yash Sir, C Language Core
  6. Java (IT Specialist): Java
  7. Python (IT Specialist): Python for Placements by Yash Sir, Python Basics
  8. OOPs (IT Specialist): Object Oriented Programming (OOPS)
  9. DBMS (IT Specialist): Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, File Organization & Indexing, Relational Algebra, Relational Calculus, Transaction Management, Concurrency Control, Database Recovery, ORDBMS, Database Security & Authorization, Query Processing & Optimization, Enhanced Data Models, Data Warehousing & Mining, Big Data Systems, NoSQL
  10. SQL (IT Specialist): SQL
  11. Software Engineering (IT Specialist): Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management
  12. Data Structure (IT Specialist): Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing
  13. Operating System (IT Specialist): Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Deadlock, Threads & Process Creation, Memory Management, Virtual Memory, Disc Scheduling, File Management, Windows OS, Linux OS, Security, Distributed Systems, Virtual Machines
  14. Compiler Design (IT Specialist): 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
  15. Computer Architecture (IT Specialist): Basics of COA, Floating Point Rep, Cache Memory Organization, Input Output Organisation, Pipelining, Instr Formats & Modes, Control Unit Design, Register Transfer and Microoperations, Multiprocessors, Programming the Basic Computer
  16. Data Communication & Networking (IT Specialist): 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
  17. Descriptive Test (Main Exam): English Writing Ability
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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