Practice question
Duration: 2 min
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Module outline
- About Course: About the Course
- Paper-2 | 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
- Paper-2 | Databases / DBMS & SQL: 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
- Paper-2 | Algorithms: Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms, Greedy Algorithms, Dynamic Programming, Minimum Spanning Trees, Shortest Path Algos
- Paper-2 | Computer Networks & Security: Introduction to CN, Data Communication, 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, Network Access Technologies, Network Security
- Paper-2 | Digital Logic: Digital Systems & Boolean Basics, Logic Gates & Hardware, Boolean Expression, Boolean Minimization, Combinational Circuit, Sequential Circuits, Number System, Number Representation, Floating Point Rep
- Paper-2 | Operating System: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Threads & Process Creation, Deadlock, Memory Management, Virtual Memory, Disc Scheduling, File Management
- 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
- Paper-2 | Computer Organization & Architecture: Basics of COA, Cache Memory Organization, Input Output Organisation, Pipelining, Instr Formats & Modes, Control Unit Design, Programming the Basic Computer
- 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-1 | General Awareness: Polity, Physics, Biology, Chemistry, Static General Knowledge, GK- Current Affairs, History, Geography, Indian Economy, Environment
- Paper-1 | Logical Reasoning: Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Data Interpretation, Blood Relations, Syllogisms, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Selection Decision Table (Decision Making), Clock, Calendar, Cubes & Dices, Directions (Direction Test), Analogy, Seating Arrangements, Analytical Reasoning (Counting Figures Reasoning)
- Paper-1 | Quantitative Aptitude: Ratio and Proportion (Ratios), Mixture and Alligation, Permutation and Combination, Number System, HCF LCM, Speed Time and Distance, Average, Age Problems, Percentage, Profit and Loss, Time and Work, Pipe and Cistern, Simple Interest and Compound Interest, Powers and Exponents (Surds and Indices), Mensuration and Geometry, Probability, Statistics, Arithmetic, Algebra
- Paper-1 | English: Vocabulary, Comprehension / Reading Comprehension / Unseen Passages (Critical Reasoning) (Paragraph Questions), Sentence Re-arrangements (Para Jumbles) (Narrative Sequencing), Sentence Correction (Error Correction), Sentence Completion (Fill in the blanks), Sentence Construction, Cloze Test (Cloze Passage)
- Coal India Previous Year Paper:
- Engineering Mathematics: Set Theory, Relations, Functions, Graph Theory, Group Theory, Propositional and Predicate Logic, Linear Algebra, Calculus
- Coal India Mock Test:
AI summary & chapters
AI Summary
An AI-generated summary of this video lecture.
The video presents a computer science problem regarding memory address calculation for arrays with non-zero or negative lower bounds. The instructor explains how to determine the memory address of a specific element when the array declaration starts at a negative index. Key parameters provided include the array range from -6 to 6, the element size of 4 bytes, and a base address of 3500. The core concept involves applying a specific formula that accounts for the offset from the lower bound rather than just the index itself. This is crucial for understanding how compilers allocate memory for arrays that do not start at index 0. The problem is clearly written in orange text at the top of the slide.
Chapters
0:00 – 1:47 00:00-01:47
The instructor begins by displaying a problem statement on the screen: "An array has been declared as follows A: array [-6-------6] of elements where every element takes 4 bytes, if the base address of the array is 3500 find the address of array[0]?" He identifies the Lower Bound (LB) as -6 and the Upper Bound (UB) as 6, writing these labels in red ink above the numbers. He notes the word size w=4 bytes. He then writes the general address calculation formula: a[K] = B + w * [K - LB]. He defines B as the base address. He substitutes the given values into this equation: Base Address B=3500, target index K=0, and LB=-6. The calculation proceeds as 3500 + 4 * [0 - (-6)], which simplifies to 3500 + 4 * 6. This results in 3500 + 24. Finally, he writes the result 3524 and underlines it in red ink as the final solution.
This lesson demonstrates the critical distinction between standard array indexing and arrays with arbitrary lower bounds. By using the formula Address = Base + WordSize * (Index - LowerBound), the instructor shows that the memory address is relative to the start of the allocated block, not index zero. This ensures correct memory access even when indices are negative, a common scenario in languages like Pascal or C with pointer arithmetic. Understanding this offset mechanism is fundamental for low-level programming and memory management tasks.