BST Practice Question
Duration: 2 min
This video lesson is available to enrolled students.
Inside: a video lesson and guided study material.
Module outline
- HPSC Interview Preparation: Interview Preparation
- Python Language: 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
- Data Structure & Algorithms: Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing, Algorithm Analysis, Sorting Algorithms, Minimum Spanning Trees, Time Complexity Analysis, Graph Theory, Shortest Path Algos
- Computer Networks: Introduction to CN, Data Communication, DLL: Access Control, DLL: Flow Control, Data Link Layer - Ethernet, Net Layer: IPv4 & Proto, Net Layer: IP Addressing, Transport Layer Services, TL: Congestion & UDP, Application Layer, Hardware basics, Network Security
- Computer System & Organisation: Basics of COA, Cache Memory Organization, Input Output Organisation, Pipelining, Instr Formats & Modes, Control Unit Design, Programming the Basic Computer
- Database Management System: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, SQL, File Organization & Indexing, Transaction Management, Concurrency Control
- Operating Systems: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Deadlock, Threads & Process Creation, Memory Management, Virtual Memory, Disc Scheduling
- Digital Logic & Circuits: Digital Systems & Boolean Basics, Logic Gates & Hardware, Boolean Expression, Boolean Minimization, Combinational Circuit, Sequential Circuits, Number System, Number Representation
- Theory Of Computation: Introduction to TOC, Deterministic FA (DFA), Non-Deterministic FA, Regular Expressions, Grammar, Regular Language Properties, Pushdown Automata & CFG, Turing Machines, Moore & Mealy Machines
- 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
- Software Engineering: Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management, Data Warehousing & Mining
- Introduction to Emerging Trends: Emerging Tech Trends
- Digital Society & Cyber Law: Society, Law & Ethics
- HPSC PGT Previous Year Paper:
- HPSC Assistant Professor Previous Year Paper:
- Live Sessions: HPSC Live Sessions, EMRS TGT/PGT Live Class
- Full Mock Test:
- HPSC PGT - MOCK Test Series:
AI summary & chapters
AI Summary
An AI-generated summary of this video lecture.
The video lecture addresses a specific scenario in Binary Search Tree (BST) deletion: removing a node that has both left and right children non-empty. The instructor explains that in this case, the inorder successor (or predecessor) must be used to replace the deleted node. He presents a multiple-choice question asking for the true statement regarding the properties of the inorder successor. The options explore whether the successor is always a leaf, has an empty left child, is an ancestor, or has an empty right child. The instructor uses a whiteboard drawing to illustrate the BST structure and the traversal logic required to find the successor.
Chapters
0:00 – 2:00 00:00-02:00
The instructor begins by stating the problem context: deleting a node with two children. He draws a BST on the whiteboard to illustrate. The tree has a root node 10, a left child 1, and a right child 15. The node 15 has a right child 20, which in turn has a right child 3. He writes the inorder traversal sequence "1 10 15 20 3" to show the order. He explains that the inorder successor of a node is the smallest node in its right subtree. He traces the path to find the successor, emphasizing that one goes to the right child and then keeps moving left until no left child exists. He analyzes the options, noting that the successor is found by going left as much as possible, meaning it cannot have a left child itself. He underlines option (B) and discusses why other options like (C) and (D) are incorrect.
2:00 – 2:10 02:00-02:10
The instructor concludes the analysis. He confirms that the inorder successor is always either a leaf node (no children) or a node with an empty left child (but potentially a right child). He explicitly marks option (B) "Inorder successor is always either a leaf node or a node with empty left child" as the correct answer. He reinforces that if the successor had a left child, that child would be smaller and thus the true successor, contradicting the definition. He circles the correct option and summarizes the key takeaway for exam preparation.
The lecture clarifies a key property of BST deletion: the inorder successor of a node with two children is guaranteed to have no left child. This is because the successor is defined as the smallest value in the right subtree, found by traversing left until a leaf or a node with only a right child is reached. This property simplifies the deletion logic, as the successor can be easily removed or spliced into the tree without violating BST properties.