AN INTRODUCTION TO POINTERS

Duration: 11 min

This video lesson is available to enrolled students.

Return to /learn/DSSSB-TGT-COMPUTER-SCIENCE-COMPLETE-COURSE/programming-data-structures-oop-java/arrays-pointers/pointer-basics-declaration-initialization-and-dereferencing/asset-an-introduction-to-pointers after enrolling

Inside: a video lesson and guided study material.

Module outline

  1. About Course: About the Course
  2. Section A: General Awareness: Polity, Physics, Biology, Chemistry, Static General Knowledge, History, Geography, Indian Economy, GK- Current Affairs, Evolution of Indian Banking (Banking & Financial Awareness), Environment
  3. Section A: General Intelligence & Reasoning ability: Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Data Sufficiency, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Analytical Reasoning (Counting Figures Reasoning), Blood Relations, Syllogisms, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Seating Arrangements, Directions (Direction Test), Puzzle Solving (Puzzles), Calendar, Clock, Cubes & Dices, Selection Decision Table (Decision Making), Logical Sequence Of Words, Crypt Arithmetic, Venn Diagram, Data Arrangement, Inequality, Analogy, Ranking, Order and Sequence, TCS NQT Advanced Reasoning Ability
  4. Section A: Arithmetical & Numerical Ability: Ratio and Proportion (Ratios), Divisibility Rules, Data Interpretation, Mixture and Alligation, Permutation and Combination, Logarithm, Number System, HCF LCM, Sequence and Series (Series), Speed Time and Distance, Percentage, Average, Profit and Loss, Simple Interest and Compound Interest, Time and Work, Pipe and Cistern, Mensuration and Geometry, Powers and Exponents (Surds and Indices), Algebra, Probability, Mental Ability, Age Problems, Partnership, Statistics, Arithmetic, Speed Mathematics and Basic Mathematics, Miscellaneous
  5. Section A: English Language & Comprehension: Vocabulary, Subject Verb Agreement (Verb Noun Agreement), Adjectives, Tenses, Comprehension / Reading Comprehension / Unseen Passages (Critical Reasoning) (Paragraph Questions), Articles, Sentence Construction, Preposition, Direct and Indirect Speech, Sentence Completion (Fill in the blanks), Sentence Re-arrangements (Para Jumbles) (Narrative Sequencing), Modals, Active Passive Voice (Voice), Sentence Correction (Error Correction), Adverb, Conjunction, Cloze Test (Cloze Passage)
  6. Section A: Hindi Language & Comprehension: भाषा, लिपि, ध्वनि, वर्ण, अक्षर, स्वर, व्यंजन, मात्रा और संयुक्ताक्षर, वर्तनी, वर्ण-विन्यास, अनुस्वार, अनुनासिक, चंद्रबिंदु और ‘र’ के रूप, शब्द, पद और शब्द-भेद, संज्ञा और सर्वनाम, विशेषण और क्रिया, लिंग, वचन, पुरुष और कारक, काल, वाच्य, वाक्य और वाक्य-भेद, संधि, समास, विलोम शब्द, पर्यायवाची शब्द, सामान्य अशुद्धियाँ, अनेक शब्दों के लिए एक शब्द, मुहावरे और लोकोक्तियाँ, अपठित गद्यांश और अपठित पद्यांश, Multi-Topic Content (Cross-Concept Material), वर्णमाला
  7. Section B: Programming, Data Structures, OOP & Java: 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, Java, OOPS with C++, Language Design, Intro to Compilers, Visual Basics, Syntax Analysis: Bottom-Up, Object Oriented Technology
  8. Section B: Computer Networks, TCP/IP & Network Security: Introduction to CN, Data Communication, DLL: Flow Control, DLL: Access Control, DLL: Error Control, Data Link Layer - Ethernet, Net Layer: IPv4 & Proto, Net Layer: IP Addressing, Transport Layer Services, TL: Congestion & UDP, Application Layer, Hardware basics, Network Access Technologies, Network Security, Society, Law & Ethics, Mobile Computing, Net Layer:Routing Protocol, Cyber Safety and Security
  9. Section B: Teaching Methodology: Child Development, Concept of Pedagogy, Theories, Inclusive Education, Experiential Pedagogy, Assessment & Evaluation, Curriculum Framework & Reforms, National Education Policy (NEP) 2020, Psychology, Teaching-Learning Process, Personality Development, Teaching Methods & Strategies, Learning and Motivation, Learners & Learning Process, Factors Affecting Teaching, Methods of Teaching, Nature, Objectives & Characteristics of Teaching, Teaching-Learning Aids & ICT Integration, Classroom Management & Communication, Evaluation, Assessment & Measurement, Curriculum & School Environment, Inclusive Education & Special Needs, Professional Development & Ethics
  10. Section B: Digital Electronics / Boolean Logic: Digital Systems & Boolean Basics, Logic Gates & Hardware, Boolean Expression, Boolean Minimization, Combinational Circuit, Sequential Circuits, Number System, Number Representation, Analog-Digital Conversion
  11. Section B: Operating Systems & Linux: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Threads & Process Creation, Deadlock, Memory Management, Virtual Memory, File Management, Disc Scheduling, Unix OS, Linux OS, Distributed Systems, Windows OS
  12. Section B: Data Base Management System: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, Relational Algebra, SQL, File Organization & Indexing, Transaction Management, Concurrency Control, Database Security & Authorization, Database Recovery, Data Warehousing & Mining
  13. Section B: Internet & Web Technologies: Website, Browser & Services, Internet Fundamentals, Web Design & Development, Protocols & Services, Web Publishing & Hosting, Server Side & Security, HTML Basics, CSS, Emerging Technologies, JavaScript-Basics, .Net Programming, Electronic Data Interchange and E-Commerce, XML
  14. Section B: Computer Fundamentals, IT Basics & Architecture: Basics of COA, Cache Memory Organization, Input Output Organisation, Register Transfer and Microoperations, Control Unit Design, Programming the Basic Computer, Terms & Abbreviations, MS Office Applications, Instr Formats & Modes, Floating Point Rep
  15. Section B: Python Language: Introduction to Python, Tokens, Variables, Data Types, I/O, Operators & Expressions, Control Flow & Looping, Collections & Strings, Functions & Modules, File Handling & Data Analysis
  16. Section B: Software Engineering: Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management, extras, Fundamentals of Systems and Information Systems
  17. Section B: Design & Analysis of Algorithms: Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms, Greedy Algorithms, Dynamic Programming, Minimum Spanning Trees, Shortest Path Algos, Advanced Algorithms
  18. Section B: Mathematics: Linear Algebra, Calculus, Trigonometry, Vectors, Set Theory, Functions, Relations, Propositional and Predicate Logic, Research Process Steps, Graph Theory
  19. Section B: Computer Graphics, Multimedia & Mobile Computing: Basics of Computer Graphics, 2-D Geometrical Transforms and Viewing, 3-D Object Representation, Geometric Transformations and Viewing, Multimedia
  20. Section B: Emerging Trends: Emerging Tech Trends, Knowledge Representation, Natural Language Processing
  21. DSSSB Previous Year Paper:
  22. Business Studies and Management: Business Communication, Business Organization and Management, Financial Accounting, Business Economics, Management Information System (MIS), Knowledge Management & New Economy
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

The video provides a foundational introduction to pointers in the C programming language, addressing why they are often considered the most difficult feature for beginners. The instructor explains that the difficulty often stems from C's specific terminology rather than the actual concept. He begins by analyzing the declaration `int i = 3;` to explain how the compiler handles memory allocation. A visual diagram illustrates that the variable `i` is a "location name" associated with a specific "location number" or address (e.g., 65524), which holds the "value at location" (3). The lecture then introduces the operators used to manipulate these addresses and values. The `&` operator is defined as the 'address of' operator, used to retrieve the memory address of a variable. Conversely, the `*` operator is introduced as the 'value at address' or 'indirection' operator, used to access the value stored at a specific address. The instructor further explains how to declare a pointer variable, such as `int *j;`, which tells the compiler that `j` will store the address of an integer. The lesson culminates in a comprehensive code example that demonstrates the relationships between variables, their addresses, and the values they hold, using multiple `printf` statements to print addresses and dereferenced values. The instructor explicitly writes out the memory map for both `i` and `j`, showing their respective addresses and contents to clarify the pointer relationship.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The video opens with a slide titled "An Introduction to Pointers". The instructor states that pointers are the feature of C that beginners find most difficult to understand. He notes that while other languages have pointers, C uses them frequently because of its clever use of them. He attributes the difficulty to terminology, specifically asking what it means when a variable is called a "pointer" and how it can point to something. He emphasizes that the difficulty has much to do with C's pointer terminology than the actual concept. The slide contains two bullet points discussing the difficulty and the terminology.

  2. 2:00 – 5:00 02:00-05:00

    The slide changes to "Pointer Notation" showing the code `int i = 3;`. The instructor explains that this declaration tells the compiler to reserve space, associate the name `i`, and store the value 3. A diagram appears showing a box with `3` inside, labeled "value at location". An arrow points to it labeled "location name" (`i`), and below is the number `65524` labeled "location number". The instructor writes `2B` next to the box to indicate the size of an integer and circles the address `65524` to emphasize it represents a memory location. He underlines the declaration `int i = 3;` in red to highlight it. Below the diagram, bullet points list the compiler actions: "Reserve space in memory...", "Associate the name i...", "Store the value 3...".

  3. 5:00 – 10:00 05:00-10:00

    The instructor displays a C program to print the address number using `printf("\nAddress of i = %u", &i);`. He explains that `&` is the 'address of' operator and `%u` is the format specifier for unsigned integers since addresses are unsigned. He introduces the `*` operator as the 'value at address' operator. He then introduces a variable `j` to store the address of `i` via `j = &i;`. A memory map shows `i` at address `65524` containing `3`, and `j` at address `65522` containing `65524`. He explains the declaration `int *j;` means `j` points to an integer, justifying the `*` as 'value at address'. He writes `int *j;` on the slide and underlines the `*`. The slide also contains bullet points explaining the `&` and `*` operators.

  4. 10:00 – 11:01 10:00-11:01

    A full program is shown to demonstrate the relationships. The code declares `int i = 3;` and `int *j;`, then assigns `j = &i;`. The instructor annotates the output of several `printf` statements next to the code. He shows that `&i` and `j` both print the address `65524`, while `&j` prints `65522`. He demonstrates that `i` prints the value `3`, and both `*(&i)` and `*j` also print `3`, effectively showing how to access the value of `i` through the pointer `j`. He writes the outputs in red next to the corresponding lines of code, including `printf("\nAddress of i = %u", &i);`, `printf("\nAddress of i = %u", j);`, and `printf("\nValue of i = %d", *j);`.

The lecture progresses logically from conceptual introduction to practical application. It starts by defining the problem (difficulty with pointers) and the solution (understanding terminology). It then visualizes memory allocation for a standard integer variable, establishing the link between a name, an address, and a value. The instructor then introduces the specific operators (`&` and `*`) that allow interaction with these memory components. Finally, the lesson consolidates these ideas by introducing a pointer variable `j` that holds the address of `i`, demonstrating through a complete code example how to print addresses and dereference pointers to access values, thereby bridging the gap between abstract concepts and executable code. The visual aids, including the memory maps and code annotations, play a crucial role in reinforcing the connection between the syntax and the underlying memory operations.

Loading lesson…