Practice Question Language

Duration: 2 min

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Module outline

  1. Discrete Mathematics: Set Theory, Relations, Functions, Graph Theory, Group Theory, Propositional and Predicate Logic
  2. DataBase Management System/DBMS: 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
  3. Digital Electronics: Digital Systems & Boolean Basics, Logic Gates & Hardware, Boolean Expression, Boolean Minimization, Combinational Circuit, Sequential Circuits, Number System, Number Representation
  4. Computer Architecture: Floating Point Rep, Cache Memory Organization, Input Output Organisation, Pipelining, Instr Formats & Modes, Control Unit Design
  5. Operating System: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Threads & Process Creation, Deadlock, Memory Management, Virtual Memory, Disc Scheduling, File Management
  6. C Language: C Fundamentals, Control Flow, Functions, Arrays & Pointers, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling
  7. Data Structures: Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing
  8. Algorithms: Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms, Greedy Algorithms, Dynamic Programming, Minimum Spanning Trees, Shortest Path Algos
  9. Computer Networks: Introduction to CN, 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
  10. Theory Of Computation/Automata Theory: Introduction to TOC, Deterministic FA (DFA), Non-Deterministic FA, Regular Expressions, Grammar, Regular Language Properties, Moore & Mealy Machines, Pushdown Automata & CFG, Turing Machines, Complexity Theory
  11. 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
  12. Engineering Mathematics: Permutation and Combination, Linear Algebra, Calculus, Probability, Statistics
  13. General Aptitude: Ratio and Proportion (Ratios), Divisibility Rules, Data Interpretation, Logarithm, Number System, HCF LCM, Sequence and Series (Series), Speed Time and Distance, Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Data Sufficiency, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Percentage, Mensuration and Geometry, Mental Ability, Arithmetic, Profit and Loss, Powers and Exponents (Surds and Indices), Average, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Syllogisms, Venn Diagram, Seating Arrangements, Blood Relations, Directions (Direction Test), Analogy, Algebra, Time and Work, Analytical Reasoning (Counting Figures Reasoning), Puzzle Solving (Puzzles), Cubes & Dices, Ranking, Order and Sequence, Mixture and Alligation, Age Problems, Clock, Selection Decision Table (Decision Making), Data Arrangement
  14. English (Verbal Aptitude): Vocabulary, Noun, Subject Verb Agreement (Verb Noun Agreement), Adjectives, Tenses, Pronoun, Preposition, Direct and Indirect Speech, Sentence Re-arrangements (Para Jumbles) (Narrative Sequencing), Sentence Completion (Fill in the blanks), Comprehension / Reading Comprehension / Unseen Passages (Critical Reasoning) (Paragraph Questions), Sentence Correction (Error Correction), Verbal Analogy (Word Based Analogy), Conjunction, Interjection, Verb, Articles, Adverb, Modals, Sentence Construction
  15. Live Classes Recordings(Earlier Batch): GATE 2026 Live Class
  16. Full Mock Test:
  17. Previous Year Papers:
  18. GATE 2026 Counselling: Counselling and Guidance Sessions
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

The video features an educational lecture on automata theory, specifically analyzing a Finite Automaton (FA) labeled M. The instructor presents a state diagram with five states: S0, S1, S2, S3, and S4. The objective is to determine the language L(M) accepted by this machine from four given multiple-choice options. The instructor begins by tracing the transitions to understand the machine's behavior. He identifies that the sequence of transitions S0 -> S1 (on 'a'), S1 -> S2 (on 'a'), S2 -> S3 (on 'b'), and S3 -> S4 (on 'b') corresponds to the input string "aabb". State S4 is a final state, indicated by a double circle, and crucially, it has self-loops for both 'a' and 'b'. This means that once the machine reaches S4, it remains in the accepting state regardless of subsequent inputs.

The instructor then systematically evaluates the options. He notes that option (a) suggests words must start with "aabb". However, since S0 has a self-loop on 'b', a string like "baabb" would transition S0 -> S0 -> S1 -> S2 -> S3 -> S4, which is accepted. Thus, the word does not need to start with "aabb". He dismisses option (c) "ending with aabb" because the loops in S4 allow any characters to follow "aabb", so a string like "aabbba" is also accepted. Similarly, option (d) "exactly one occurrence" is rejected because the loops in S4 allow the machine to accept strings with multiple occurrences of "aabb", such as "aabbaabb". Finally, he concludes that option (b) "Set of all words having aabb as a sub word" is the correct description. The machine accepts any string that contains "aabb" as a substring, as reaching S4 guarantees acceptance. The instructor underlines option (b) to confirm the answer.

Chapters

  1. 0:00 – 1:36 00:00-01:36

    The instructor introduces the problem of finding the language L(M) for the given machine M. He displays the state diagram with states S0 through S4. He traces the path for "aabb" (S0->S1->S2->S3->S4) and notes the final state S4 has loops on 'a' and 'b'. He discusses the options, eliminating (a) because S0 loops on 'b', eliminating (c) and (d) because S4 loops allow any suffix or multiple occurrences. He concludes that the machine accepts any word containing "aabb" as a substring, underlining option (b).

The lecture demonstrates how to analyze a Finite Automaton to determine its accepted language. By tracing paths and observing state transitions, particularly final states with self-loops, one can deduce that the machine accepts any string containing a specific substring. The key insight is that once the substring "aabb" is recognized, the machine enters a "trap" or "accepting" state that never leaves, effectively matching the language of strings containing that substring.

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