Stack recursion Practice questions
Duration: 3 min
This video lesson is available to enrolled students.
Inside: a video lesson and guided study material.
Module outline
- About the course: About the Course
- Mathematical Aptitude: Number System, HCF LCM, Divisibility Rules, Percentage, Ratio and Proportion (Ratios), Average, Profit and Loss, Time and Work, Mensuration and Geometry, Simple Interest and Compound Interest, Speed Time and Distance, Age Problems, Mixture and Alligation, Algebra, Powers and Exponents (Surds and Indices), Pipe and Cistern, Trigonometry, Statistics, Data Interpretation, Arithmetic, Number System & Place Value, Factors, Multiples, Divisibility, HCF & LCM, Coordinates & Graphs, Higher Mathematics — Trigonometry, Quadratics, Polynomials, Progressions, Statistics, Logarithms
- Logical Reasoning: Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Analogy, Blood Relations, Directions (Direction Test), Ranking, Order and Sequence, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Seating Arrangements, Syllogisms, Venn Diagram, Puzzle Solving (Puzzles), Logical Sequence Of Words, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Analytical Reasoning (Counting Figures Reasoning), Cubes & Dices, Calendar, Clock
- General Knowledge: Physics, Chemistry, Biology, History, Geography, Polity, Indian Economy, GK- Current Affairs, Static General Knowledge
- Art of Teaching: Nature, Objectives & Characteristics of Teaching, Learners & Learning Process, Factors Affecting Teaching, Methods of Teaching, Classroom Management & Communication, Teaching-Learning Aids & ICT Integration, Evaluation, Assessment & Measurement, Professional Development & Ethics, Policies, Acts & Contemporary Issues, Curriculum & School Environment, Guidance, Counselling & Mental Health, Inclusive Education & Special Needs, Micro-Teaching & Teaching Skills, Lesson Planning
- Environmental Science: Environment
- Unit 1 | Digital Electronics: Digital Systems & Boolean Basics, Logic Gates & Hardware, Boolean Expression, Boolean Minimization, Combinational Circuit, Sequential Circuits, Number System, Number Representation
- Unit 2 | COA: Basics of COA, Floating Point Rep, Cache Memory Organization, Input Output Organisation, Instr Formats & Modes, Control Unit Design, Register Transfer and Microoperations, Programming the Basic Computer
- Unit 3 | C Programming: C Fundamentals, Control Flow, Functions, Arrays & Pointers, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling
- Unit 3 | Data Structures: Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing
- Unit 4 | Algorithms: Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms, Dynamic Programming, Minimum Spanning Trees, Shortest Path Algos, Advanced Algorithms
- Unit 5 | Operating System: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Threads & Process Creation, Deadlock, Memory Management, Virtual Memory, Disc Scheduling, File Management
- Unit 6 | Database Management System: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, File Organization & Indexing, Relational Algebra, SQL, Transaction Management, Concurrency Control
- Unit 7 | Computer Networks: 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
- Unit 8 | Software Engineering: Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management
- Unit 9 | Object Oriented Programming: OOPS with C++
- Unit 10 | Web Development: HTML Basics, CSS, JavaScript-Basics, XML
- Unit 11 | 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
- Unit 12 | IoT: Emerging Tech Trends, Cloud Computing, कंप्यूटर नेटवर्क / Computer Networks
- Unit 13 | Artificial Intelligence: Approaches to AI, Search Algorithms, Game Playing, Knowledge Representation, Natural Language Processing, Artificial Neural Networks, Genetic Algorithms
- Unit 14 | E-Commerce: Electronic Data Interchange and E-Commerce, Role of Internet and Web Services, Security in Mobile and Wireless Computing, Physical Security and Cryptography Basics, Cyber Safety and Security
- Unit 15 | Multimedia: Multimedia
- Unit 16 | Python: Introduction to Python, Tokens, Variables, Data Types, I/O, Operators & Expressions, Control Flow & Looping, Collections & Strings, Functions & Modules, File Handling & Data Analysis, DSA using Python
- Full Length Mock Tests — General Paper:
- Full Length Mock Tests — Computer Science (Paper II):
AI summary & chapters
AI Summary
An AI-generated summary of this video lecture.
The video presents a computer science problem asking to identify the functionality of a given recursive C function. The function fun(int x, int y) takes two integer arguments. The instructor analyzes the code structure, identifying a base case where y equals 0 returns 0, and a recursive step that adds x to the result of fun(x, y-1). To understand the behavior, the instructor sets up a concrete example with x = 2 and y = 4. He manually traces the recursion, expanding the function calls step-by-step until the base case is reached. After calculating the final result, he evaluates four multiple-choice options to find the mathematical equivalent of the function's operation.
Chapters
0:00 – 2:00 00:00-02:00
The segment begins with the problem statement and code display. The instructor underlines the condition if (y == 0) and the return statement return 0. He then introduces test values x = 2 and y = 4 to trace the execution. He writes fun(2, 4) on the board and begins expanding the recursive calls. The expansion shows Return (2 + fun(2, 3)), followed by Return (2 + fun(2, 2)), and Return (2 + fun(2, 1)). The tracing continues until the base case Return (2 + fun(2, 0)) is reached. The instructor underlines y == 0 to emphasize the stopping condition. He then starts the backtracking process, calculating 2 + 0 = 2 for the base case return value. This section establishes the recursive structure and begins the manual execution trace.
2:00 – 3:24 02:00-03:24
The instructor continues the backtracking calculation from the previous window. He computes the return values for each recursive level: fun(2, 1) returns 2, fun(2, 2) returns 4, fun(2, 3) returns 6, and finally fun(2, 4) returns 8. With the result 8 established, he systematically checks the provided options. He calculates x + y as 6, x + x*y as 10, x*y as 8, and x^y as 16. He marks option (A) and (B) as incorrect. He identifies that option (C) x*y matches the calculated result of 8. He places a checkmark next to option (C) and crosses out the others, confirming that the function performs multiplication. The video concludes with the correct answer identified.
The lecture effectively demonstrates a standard technique for analyzing recursive algorithms: manual tracing with concrete inputs. By substituting specific values, the abstract recursion becomes a concrete arithmetic sequence. The instructor shows that adding x repeatedly y times is mathematically equivalent to multiplying x by y. This method of tracing execution flow and comparing results against options is a crucial skill for solving recursion problems in computer science exams. It highlights the importance of understanding base cases and recursive steps in algorithm design.