Understanding Follow Function

Duration: 7 min

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Module outline

  1. General Intelligence & Reasoning: Analogy, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Blood Relations, Directions (Direction Test), Ranking, Order and Sequence, Logical Sequence Of Words, Syllogisms, Venn Diagram, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Selection Decision Table (Decision Making), Data Sufficiency, Puzzle Solving (Puzzles), Data Arrangement, Cubes & Dices, Calendar, Clock, Arithmetic, Number System, HCF LCM, Verbal Analogy (Word Based Analogy), Visual Recognition and Figure Completion, Paper Folding and Cutting, Transformation of Shapes, Clocks and Calendars, Direction Sense, Cubes and Dice, Patterns in Two-Dimensional Figures, Seating Arrangements, Analogy and Classification, Logical Deduction and Induction, Alphabet and Word Tests, Mathematical Operations, Series Completion, Simplification and Approximation, Coding and Decoding, Numerical Reasoning, Assembling and Grouping of Shapes, Three-Dimensional Patterns and Visualization, Vocabulary, Number System, Averages, Mixtures and Alligation, Simple and Compound Interest, Percentages, Algebra, Speed, Time and Distance, Seating and Arrangement Puzzles, Traverse Surveying, Order, Ranking and Sequence, Constraint Puzzles, Syllogisms and Venn Diagrams, Reading Comprehension, Critical Reasoning, Permutations and Combinations, Narrative Sequencing, Project Monitoring, Resources and Safety, Profit, Loss and Discount, Ratio and Proportion, Time and Work, Mensuration, Data Interpretation, Powers, Surds and Logarithms, Sequences and Series, Articles and Determiners, Sentence Completion, Data Sufficiency, Blood Relations, Simple Interest and Compound Interest, Mixture and Alligation, Sequence and Series (Series), Speed Time and Distance, Algebra, Profit and Loss, Powers and Exponents (Surds and Indices), Permutation and Combination
  2. General Awareness: Physics, Chemistry, Biology, History, Geography, Polity, Indian Economy, Environment, Static General Knowledge, GK- Current Affairs, Artificial Intelligence, MS Office Applications, Terms & Abbreviations, Keyboard Shortcuts, Evolution of Indian Banking (Banking & Financial Awareness), Emerging Tech Trends
  3. Engineering Mathematics: Set Theory, Relations, Functions, Graph Theory, Group Theory, Propositional and Predicate Logic, Linear Algebra, Calculus, Probability, Statistics, Signal Space and Optimum Detection, Probability, Statistics
  4. Digital Logic: Digital Systems & Boolean Basics, Logic Gates & Hardware, Boolean Expression, Boolean Minimization, Combinational Circuit, Sequential Circuits, Number System, Number Representation, Floating Point Rep, Number Systems and Codes, Registers and Counters, Boolean Algebra and Logic Gates, Microprocessors and Microcontrollers, Logic Families and CMOS Logic, Microprocessors, Logic Gates and Boolean Algebra, Minimization of Boolean Functions, Timing, Hazards and Testing, Logic Families, Combinational Logic Design, Arithmetic Circuits, Waveform Generators and Timer Circuits, Semiconductor Memories and Programmable Logic Devices, Combinational Logic Circuits, Latches and Flip-Flops, Finite State Machines, Sequential Circuits and State Machines, Minimization of Boolean Functions, Arithmetic Circuits, Latches and Flip-Flops, Number Systems and Codes, Registers and Counters
  5. Computer Organisation & Architecture: Basics of COA, Cache Memory Organization, Input Output Organisation, Pipelining, Instr Formats & Modes, Control Unit Design, Programming the Basic Computer, Register Transfer and Microoperations, Semiconductor Memories and Programmable Logic, Processor Organization and Instructions, Memory Hierarchy and Input/Output, Registers and Counters
  6. Programming & Data Structures: C Fundamentals, Control Flow, Functions, Arrays & Pointers, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling, Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing, HTML Basics, OOPS with C++, Java, Object Oriented Technology
  7. Databases: 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, Database Recovery, Database Security & Authorization
  8. Algorithms: Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms, Greedy Algorithms, Dynamic Programming, Minimum Spanning Trees, Shortest Path Algos
  9. Theory of Computation: 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
  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. Operating System: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Threads & Process Creation, Deadlock, Memory Management, Virtual Memory, Disc Scheduling, File Management, Security, Windows OS, Distributed Systems, Unix OS, Linux OS
  12. 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, Data Communication, Website, Browser & Services, Web Design & Development, Network Security, Cyber Threats and Malware Attacks, Cyber Safety and Security
  13. Full Length Mock Tests:
  14. Sectional Tests:
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

This educational video provides a detailed lecture on computing Follow sets within the context of Context-Free Grammars and compiler design. The instructor begins by defining Follow(A) as the set of terminals that can appear immediately to the right of a non-terminal A in any sentential form. He systematically presents four fundamental rules used to calculate these sets, covering cases for start symbols, productions with non-epsilon suffixes, and productions where the suffix can derive epsilon. The lecture then transitions into practical applications, solving examples of increasing complexity to demonstrate the application of these rules.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The lecture begins with the definition of Follow(A) displayed on the slide. The instructor explains that Follow(A) contains terminals following A in sentential grammars. He lists four specific rules: Rule 1 states that if A is the start symbol, Follow(A) includes the end marker $. Rule 2 applies when A is followed by a non-epsilon beta, setting Follow(A) to First(beta). Rule 3 handles the case where A is the last symbol in a production, equating Follow(A) to Follow(S). Rule 4 addresses the scenario where A is followed by a beta that can derive epsilon, combining First(beta) and Follow(S). The instructor uses hand-drawn diagrams with arrows and lines to visually represent derivations and the position of terminals relative to non-terminals.

  2. 2:00 – 5:00 02:00-05:00

    Next, the presenter moves to a simple example where S -> epsilon. He determines First(S) is {epsilon} and Follow(S) is {$} because S is the start symbol. He then introduces a slightly more complex grammar: S -> aA and A -> bA / epsilon. He calculates First(S) as {a} and First(A) as {b, epsilon}. For Follow sets, he establishes Follow(S) as {$}. To find Follow(A), he notes that A appears at the end of the production S -> aA. Applying Rule 3, he concludes that Follow(A) must equal Follow(S), which is {$}. He writes these values clearly on the slide to reinforce the concept.

  3. 5:00 – 7:06 05:00-07:06

    Subsequently, the class analyzes a grammar with multiple productions: S -> AaBb / BbAa, with A -> epsilon and B -> epsilon. The instructor calculates Follow(S) as {$}. For Follow(A), he observes that A is followed by 'a' in both productions, so Follow(A) = {a}. Similarly, B is followed by 'b' in both productions, so Follow(B) = {b}. Finally, he introduces a standard arithmetic expression grammar: E -> E+T / T, T -> T*F / F, F -> (E) / id. He begins calculating Follow sets for this recursive grammar. He determines Follow(E) = {$, +} based on the start symbol and the '+' in E -> E+T. He finds Follow(T) = {*, $, +} by combining the end marker, the '*' from T -> T*F, and the '+' from E -> E+T. He writes Follow(F) = {*, $, +}, indicating the terminals that can follow F in the derived strings.

The video effectively bridges theoretical definitions with practical calculation methods. By starting with abstract rules and moving to concrete examples, the instructor demonstrates how to handle epsilon productions and recursive structures. The progression from simple start symbol cases to complex arithmetic grammars provides a comprehensive guide for students learning to construct parsing tables or analyze grammars.

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