Recursive Functions

Duration: 7 min

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Module outline

  1. Communication Round: Vocabulary, Subject Verb Agreement (Verb Noun Agreement), Tenses, Comprehension / Reading Comprehension / Unseen Passages (Critical Reasoning) (Paragraph Questions), Cloze Test (Cloze Passage), Sentence Correction (Error Correction), Sentence Completion (Fill in the blanks), Sentence Re-arrangements (Para Jumbles) (Narrative Sequencing), Direct and Indirect Speech, Active Passive Voice (Voice), Verbal Analogy (Word Based Analogy), Articles, Preposition, Conjunction, Sentence Construction, English Writing Ability, Communication Assessment
  2. Quantitative Aptitude: Ratio and Proportion (Ratios), Divisibility Rules, Data Interpretation, Mixture and Alligation, Permutation and Combination, Logarithm, Number System, HCF LCM, Speed Time and Distance, Percentage, Average, Powers and Exponents (Surds and Indices), Time and Work, Mensuration and Geometry, Age Problems, Pipe and Cistern, Probability, Profit and Loss, Simple Interest and Compound Interest, Algebra
  3. Analytical and Logical Reasoning: Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Data Sufficiency, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Directions (Direction Test), Ranking, Order and Sequence, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Selection Decision Table (Decision Making), Logical Sequence Of Words, Puzzle Solving (Puzzles), Syllogisms, Seating Arrangements, Calendar, Clock, Blood Relations, Cubes & Dices, Venn Diagram, Analytical Reasoning (Counting Figures Reasoning)
  4. Cognizant Gaming Aptitude: Gamified / Game Based Aptitude
  5. Java (Cluster 1): Java
  6. ANSI SQL MySQL (Cluster 1,2,3): SQL
  7. HTML, CSS, JavaScript (Cluster 1,3): HTML, CSS, JavaScript
  8. Python (Cluster 2): Python for Placements by Yash Sir
  9. Cloud Fundamentals (Cluster 2): Emerging Tech Trends
  10. C# (Cluster 3): C#
  11. OOPs: Object Oriented Programming (OOPS)
  12. Technical Assessment (Coding): Coding Questions by Yash Sir, C Programming by Yash Sir, Programming in C++, Pseudo Codes
  13. Data Structures: Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing
  14. DBMS: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, File Organization & Indexing, Relational Algebra, Relational Calculus, Transaction Management, Concurrency Control, Database Recovery, ORDBMS, Database Security & Authorization, Query Processing & Optimization, Enhanced Data Models, Data Warehousing & Mining, Big Data Systems, NoSQL
  15. Operating Systems: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Deadlock, Threads & Process Creation, Memory Management, Virtual Memory, Disc Scheduling, File Management, Windows OS, Linux OS, Security, Distributed Systems, Virtual Machines
  16. 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, Hardware basics, Network Security, Mobile Technology, Cloud Computing and IoT, Cyber and Info Security
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

The video lecture analyzes a recursive pseudo-code function named `Print_array(a, i, j)` to determine its output. The instructor begins by defining the function's logic: a base case where `i == j` prints the current element and returns, and a recursive step that calls the function with `i+1` before printing the current element `a[i]`. He sets up a concrete example using an array `a` with indices 0 through 4, populating it with values 10, 12, 18, 22, and 11. The specific function call analyzed is `print_array(a, 0, 3)`. Through a detailed trace on the whiteboard, the instructor demonstrates how the recursion unwinds, resulting in the array elements being printed in reverse order of their indices within the specified range.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The instructor introduces the problem by displaying the pseudo-code for `void Print_array(a, i, j)`. He draws a diagram of an array `a` with indices 0 to 4. Initially, he writes memory addresses like 1000, 1004, 1008, 1012, 1016 above the array cells, but then corrects this to actual integer values: 10, 12, 18, 22, 11. He writes the initial function call `print_array(a, 0, 3)` on the board, setting the stage for the trace where `i` starts at 0 and `j` is 3.

  2. 2:00 – 5:00 02:00-05:00

    The instructor traces the recursive execution step-by-step. He writes down the sequence of calls: `print_array(a, 0, 3)` calls `print_array(a, 1, 3)`, which calls `print_array(a, 2, 3)`, which finally calls `print_array(a, 3, 3)`. At this point, the condition `i == j` (3 == 3) is true. He circles the base case logic, noting that `a[3]` (value 22) is printed first. He then explains the return process, showing that after the recursive call returns, the code proceeds to the `printf` statement below it. This causes `a[2]` (18) to be printed, followed by `a[1]` (12), and finally `a[0]` (10) as the stack unwinds back to the initial call.

  3. 5:00 – 6:40 05:00-06:40

    In the final segment, the instructor consolidates the results of the trace. He writes the final output sequence `22 18 12 10` at the bottom of the whiteboard. He emphasizes that the placement of the `printf` statement *after* the recursive call is the key factor causing the reverse order output. He circles the relevant lines of code to reinforce that the printing happens on the way back up the recursion stack, effectively reversing the order of indices from 0 to 3.

The lecture effectively demonstrates the concept of post-order traversal in recursion. By placing the print statement after the recursive call, the function delays printing until the base case is reached and the stack begins to unwind. This results in the output sequence being the reverse of the index progression from `i` to `j`. The instructor uses a concrete array example to visualize the stack depth and the specific values printed at each return step.

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