Stack_Practice Questions
Duration: 1 min
This video lesson is available to enrolled students.
Inside: a video lesson and guided study material.
Module outline
- English Comprehension/Verbal Ability: Comprehension / Reading Comprehension / Unseen Passages (Critical Reasoning) (Paragraph Questions), Vocabulary, Sentence Correction (Error Correction), Sentence Completion (Fill in the blanks), Sentence Re-arrangements (Para Jumbles) (Narrative Sequencing), Subject Verb Agreement (Verb Noun Agreement), Tenses, Verb, Articles, Preposition, Conjunction, Pronoun, Noun, Adjectives, Adverb, Modals, Cloze Test (Cloze Passage), Active Passive Voice (Voice), Direct and Indirect Speech, Sentence Construction
- Logical Ability: Coding Decoding, Directions (Direction Test), Analogy, Inequality, Data Sufficiency, Series (Number and Letter Series) (Numerical Relations and Reasoning), Syllogisms, Seating Arrangements, Puzzle Solving (Puzzles), Blood Relations, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Ranking, Order and Sequence, Logical Sequence Of Words, Data Arrangement, Venn Diagram, Calendar, Clock
- Quantitative Ability: Logarithm, Permutation and Combination, Probability, Profit and Loss, Speed Time and Distance, Mixture and Alligation, Partnership, Simple Interest and Compound Interest, Percentage, Ratio and Proportion (Ratios), Average, Time and Work, Pipe and Cistern, Number System, Divisibility Rules, HCF LCM, Algebra, Powers and Exponents (Surds and Indices), Mensuration and Geometry, Age Problems, Data Interpretation, Sequence and Series (Series)
- Basic Analytical Ability: Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Analytical Reasoning (Counting Figures Reasoning), Cubes & Dices, Selection Decision Table (Decision Making)
- Computer Programming: Pseudo Codes, Coding Questions by Yash Sir, C Programming by Yash Sir, Programming in C++, Java, Python for Placements by Yash Sir
- DBMS (Computer Science): Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Transaction Management, Concurrency Control, Database Security & Authorization
- SQL (Computer Science): SQL
- OS (Computer Science): Introduction to OS, Process Management, CPU Scheduling, Deadlock, Process Synchronization, Threads & Process Creation, Memory Management, Virtual Memory, File Management
- Computer Networks (Computer Science): 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
- Data Structures (Computer Science): Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing
- OOPs (Computer Science): Object Oriented Programming (OOPS)
- Software Engineering (Computer Science): Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management
- SVAR Conversational - Spoken English: Communication Assessment
- HR Interview: MR & HR Interview Preparation
AI summary & chapters
AI Summary
An AI-generated summary of this video lecture.
The video presents a problem in data structures: determining the minimum number of stacks required to implement a queue, given the constraint that no other data structures like arrays or linked lists are available. The instructor, Sanchit Jain, identifies the correct answer as two stacks. He visually demonstrates the logic by drawing two stacks and a queue containing elements 'a', 'b', 'c', and 'd'. He explains that elements are pushed onto the first stack and then transferred to the second stack to reverse their order, enabling First-In-First-Out (FIFO) operations. This ensures the oldest element is at the top of the second stack for removal.
Chapters
0:00 – 0:59 00:00-00:59
The video opens with a text-based question on the screen asking how many stacks are needed to implement a queue without arrays or linked lists. The options provided are (A) 1, (B) 2, (C) 3, and (D) 4. The instructor marks option (B) 2 as the correct answer. He proceeds to draw two vertical rectangular boxes on the whiteboard to represent the two stacks. He then draws a horizontal box above them representing a queue with elements 'a', 'b', 'c', 'd' inside. He illustrates the enqueue process by writing 'a', 'b', 'c', 'd' into the first stack from bottom to top. He then explains the dequeue process, showing how elements must be moved from the first stack to the second stack. This transfer reverses the order, placing 'a' at the top of the second stack, allowing it to be popped first.
The lecture provides a clear, visual explanation of a classic data structure problem. By using two stacks, the instructor shows how to overcome the Last-In-First-Out (LIFO) limitation of a single stack to achieve the First-In-First-Out (FIFO) requirement of a queue. This technique is a standard solution often tested in computer science examinations.