WHAT IS FUNCTIONS

Duration: 9 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 provides a foundational lecture on functions in the C programming language. It begins by defining a function as a self-contained block of statements that performs a coherent task, using the analogy of hiring a person to do a specific job. The instructor explains the mechanism of "calling" a function, where control transfers from the calling function (typically main) to the called function and returns upon completion. The lesson covers the mandatory presence of the main function in every C program and demonstrates that the order of function definition does not dictate the order of execution. Finally, it distinguishes between library functions, which are pre-written and provided by the compiler, and user-defined functions created by the programmer. This lecture serves as an introduction to modular programming in C.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The video starts with a "Break" slide before transitioning to a slide titled "1 – What is a Function". The instructor introduces the concept by stating, "Knowingly or unknowingly we rely on so many persons for so many things." He compares human reliance on others (like a mechanic or gardener) to a computer program's need for assistance. The slide text explains that a computer program "cannot handle all the tasks by itself" and instead "requests other program like entities—called ‘functions’ in C—to get its tasks done." This section establishes the conceptual basis for why functions are necessary in programming. The instructor emphasizes that even though man is an intelligent species, he "cannot perform all of life’s tasks all alone." He mentions that a program finds itself in a similar situation.

  2. 2:00 – 5:00 02:00-05:00

    The instructor presents a code example where main() calls message(). He explains that when main() calls message(), "control passes to the function message(). The activity of main() is temporarily suspended." He illustrates this with a red arrow pointing from message(); in main() to the message() definition. He then shows a more complex example where main() calls italy(), brazil(), and argentina(). He draws red circles around each function block to emphasize they are separate entities. He concludes this section by stating, "If a C program contains more than one function, then one (and only one) of these functions must be main(), because program execution always begins with main()." He also notes that "Any C program contains at least one function." He explains that if a program contains only one function, it must be main().

  3. 5:00 – 9:20 05:00-09:20

    The lecture addresses the order of function definitions. A code snippet shows main() calling message1() and message2(), but message2() is defined before message1(). The instructor circles the function blocks and states, "The order in which the functions are defined in a program and the order in which they get called need not necessarily be same." He then summarizes the two types of functions: "Library functions Ex. printf(), scanf() etc." and "User-defined functions Ex. argentina(), brazil() etc." He explains that library functions are "commonly required functions grouped together and stored in what is called a Library," written by compiler writers, whereas user-defined functions are created by the programmer. He adds that "The procedure of calling both types of functions is exactly same." He also mentions that "Almost always a compiler comes with a library of standard functions."

The lesson systematically builds an understanding of C functions from concept to implementation. It moves from the high-level analogy of outsourcing tasks to the technical details of control flow and function calls. By demonstrating that definition order is flexible and distinguishing between standard library and custom functions, the instructor provides a comprehensive overview of how functions structure a C program, preparing students for writing modular and efficient code. The progression from simple examples to more complex calls ensures a clear understanding of the core concepts.

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