Practice Problem on First Function
Duration: 8 min
This video lesson is available to enrolled students.
Inside: a video lesson and guided study material.
Module outline
- About Course: About the Course
- Paper 1 | General Studies: State Wise GK
- Paper 1 | Information and Communication Technology: Role of Internet and Web Services, Security in Mobile and Wireless Computing
- Paper 1 | Current Affairs: GK- Current Affairs
- Paper 2 | Discrete Mathematical Structure: Digital Systems & Boolean Basics, Logic Gates & Hardware, Boolean Expression, Boolean Minimization, Set Theory, Relations, Functions, Graph Theory, Group Theory, Propositional and Predicate Logic, Probability
- Paper 2 | Digital Computer Organization And Architecture: Number System, Number Representation, Sequential Circuits, Combinational Circuit, Basics of COA, Floating Point Rep, Cache Memory Organization, Input Output Organisation, Pipelining, Instr Formats & Modes, Register Transfer and Microoperations, Control Unit Design, Programming the Basic Computer
- Paper 2 | C Programming: C Fundamentals, Control Flow, Functions, Arrays & Pointers, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling
- Paper 2 | Programming Languages & Object-Oriented Programming Concepts: Java, OOPS with C++, Java Fundamentals, Array, String, IO & References
- Paper 2 | Python: Introduction to Python, Tokens, Variables, Data Types, I/O, Operators & Expressions, Control Flow & Looping, Collections & Strings, Functions & Modules, File Handling & Data Analysis
- Paper 2 | Data Structure And Algorithms: Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing, Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms, Greedy Algorithms, Minimum Spanning Trees, Advanced Algorithms
- Paper 2 | Operating System: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Deadlock, Threads & Process Creation, Memory Management, Virtual Memory, Disc Scheduling, File Management, Unix OS
- Paper 2 | 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
- Paper 2 | 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
- Paper 2 | Database Management System: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, Relational Algebra, SQL, Transaction Management, Concurrency Control, Database Recovery, Database Security & Authorization, Enhanced Data Models
- Paper 2 | Computer Network And Information Security: Introduction to CN, Data Communication, Application Layer, Hardware basics, Cyber Threats and Malware Attacks, Network Security, 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
- Paper 2 | Software Engineering: Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management
- Paper 2 | Current Trends & Technologies: Emerging Tech Trends, Approaches to AI, Search Algorithms, Game Playing, Knowledge Representation, Planning, Multi Agent Systems, Fuzzy Sets, Natural Language Processing, Artificial Neural Networks, Genetic Algorithms, Artificial Intelligence, Data Warehousing & Mining, Electronic Data Interchange and E-Commerce, Terms & Abbreviations
- Paper 2 | Full Length Mock Tests:
AI summary & chapters
AI Summary
An AI-generated summary of this video lecture.
This educational video provides a detailed lecture on Compiler Design, specifically focusing on the calculation of First and Follow sets for context-free grammars. The instructor systematically works through multiple examples of increasing complexity, demonstrating how to derive these sets for various production rules. The session begins with simple recursive grammars involving epsilon productions and progresses to standard arithmetic expression grammars. The lecture concludes with a theoretical overview of the formal rules used to calculate First sets for both terminals and non-terminals.
Chapters
0:00 – 2:00 00:00-02:00
The instructor begins with a grammar: S -> AaB / Bb, A -> bA / epsilon, B -> cB / epsilon. He calculates First(A) as {b, epsilon} and First(B) as {c, epsilon}. For First(S), he analyzes the productions S -> AaB and S -> Bb. Since A can derive epsilon, 'a' is added to First(S). Since B can derive epsilon, 'b' is added. The final set written on the board is First(S) = {b, a, c}. He then transitions to a second example: S -> AB, A -> a / epsilon, B -> b / epsilon. He determines First(A) = {a, epsilon} and First(B) = {b, epsilon}. He explains that First(S) becomes {a, b, epsilon} because both A and B can derive epsilon, allowing the derivation to continue or terminate early.
2:00 – 5:00 02:00-05:00
The lecture progresses to a more complex chain: S -> ABCDE. The non-terminals A, B, C, and E have epsilon productions (A -> a/epsilon, B -> b/epsilon, C -> c/epsilon, E -> e/epsilon), while D -> d is a terminal production. The instructor calculates First(A)={a, epsilon}, First(B)={b, epsilon}, First(C)={c, epsilon}, First(D)={d}, and First(E)={e, epsilon}. He determines First(S) = {a, b, c, d} because the derivation stops at D. Next, he analyzes S -> aAB / BA, A -> BA / epsilon, B -> AB / a / epsilon. He finds First(B) = {a, epsilon} and First(A) = {a, epsilon}. Consequently, First(S) is derived as {a, epsilon} based on the union of the first symbols of the productions.
5:00 – 8:28 05:00-08:28
The instructor presents S -> AA, A -> aA, A -> b. He calculates First(S) = {a, b} and First(A) = {a, b}. He then moves to a list grammar: S -> (L) / a, L -> SL', L' -> ,SL' / epsilon. He calculates First(L') = {,, epsilon}. He then tackles a standard arithmetic expression grammar: E -> TE', E' -> +TE' / epsilon, T -> FT', T' -> *FT' / epsilon, F -> (E) / id. He calculates First(F) = {(, id}, First(T') = {*, epsilon}, First(T) = {(, id}, First(E') = {+, epsilon}, and First(E) = {(, id}. Finally, he shows a slide defining the rules for First(alpha), covering terminals, epsilon productions, and sequences of non-terminals, explaining that First(alpha) is the set of all terminals that may begin in any sentential form derived from alpha.
The video effectively bridges practical examples with theoretical definitions. By starting with simple recursive structures and moving to complex chains and standard expression grammars, the instructor demonstrates the iterative nature of First set calculation. The final slide reinforces the logic used throughout the examples, providing a formal framework for students to apply to new problems. The progression from specific calculations to general rules ensures a comprehensive understanding of the topic.