Bottom Up Parser Fundamentals Part-1

Duration: 8 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.

The video lecture provides a comprehensive introduction to Bottom-Up Parsing within the field of Compiler Design. It begins by situating Bottom-Up parsers within a hierarchical classification of all parsers, specifically distinguishing them from Top-Down parsers. The instructor details the sub-categories of Bottom-Up parsers, including L-R parsers (LR(0), SLR(1), CLR(1), LALR(1)) and Operator Precedence parsers. The core of the lecture defines the Bottom-Up process as constructing a parse tree from the leaves (children) up to the root. This is illustrated with a specific grammar example (S -> aABc) and input string (w = abcdc), where the instructor manually draws the tree and identifies 'handles' like 'bc' and 'd'. The concept of 'Handle Pruning' is introduced as the mechanism of replacing a handle with its corresponding non-terminal. The lecture concludes by comparing the efficiency of Bottom-Up parsing against Top-Down parsing, citing time complexities of O(n^3) versus O(n^4), and begins a new example to demonstrate the parsing table structure.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The instructor starts with a visual flowchart classifying parsers into Top-Down and Bottom-Up categories. He focuses on the Bottom-Up branch, pointing out that it divides into 'L-R Parser' and 'Operator Precedence Parser'. He specifically highlights the four types of L-R parsers listed below: LR(0), SLR(1), CLR(1), and LALR(1). He verbally notes that Operator Precedence parsers are typically used for ambiguous grammars, whereas L-R parsers are designed for unambiguous grammars. This section establishes the taxonomy of parsing techniques before diving into the specific mechanics of Bottom-Up parsing. The on-screen text 'Knowledge Gate Educator Sanchit Jain Sir' is visible at the bottom left. Red arrows are drawn on the screen to indicate the hierarchy.

  2. 2:00 – 5:00 02:00-05:00

    The instructor presents a slide defining Bottom-Up parsing as the process of constructing a parse tree in a Bottom-Up manner, meaning starting from the children and proceeding towards the root. He provides a concrete example with the grammar rules S -> aABc, A -> b / bc, and B -> d, along with the input string w = abcdc. On the screen, he draws a parse tree diagram, starting with the terminal symbols a, b, c, d, c at the bottom. He circles the substrings 'bc' and 'd', identifying them as 'handles'. He explains that the process of finding a handle and replacing it with its Left-Hand Side (LHS) variable is called 'Handle Pruning'. He also mentions that Bottom-Up Parsing is alternatively known as 'Shift-Reduced Parsing'. The slide text explicitly states 'Handle: - Substring of the i/p string that matches with RHS of any production, is called as Handle.' The input string 'w = abcdc' is underlined in red.

  3. 5:00 – 8:17 05:00-08:17

    The lecture shifts to the performance characteristics of Bottom-Up Parsing. The instructor states that Bottom-Up parsing is faster and more efficient than Top-Down Parsing. He writes on the board to compare time complexities, noting 'Top -> O(n^4)' and 'Bottom -> O(n^3)'. He explains that Bottom-Up Parsing simulates the reverse of a Right Most Derivation. To further illustrate the concept, he introduces a new grammar: S -> AA and A -> aA / b. He then draws a table with three columns labeled 'Stack', 'i/p', and 'Action', preparing to demonstrate the step-by-step parsing process using this new example. The slide text mentions 'BUP can be constructed for both Ambiguous & Unambiguous grammar' and 'Handle pruning is the overhead for bottom-UP-parsing.'

The video provides a structured introduction to Bottom-Up Parsing, moving from a high-level classification of parsers to a detailed explanation of the parsing mechanism. It effectively uses visual aids like flowcharts and hand-drawn parse trees to clarify abstract concepts such as 'handles' and 'handle pruning'. By comparing time complexities and introducing the parsing table structure, the lecture bridges the gap between theoretical definitions and practical implementation, preparing students for more advanced topics like LR parsing tables.

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