DSA & Algorithms
38 articles in this topic
AVL Trees for GATE: Rotations, Height Bounds and Minimum-Node Numericals Solved
Choose LL, RR, LR or RL from the insertion path, then solve AVL height questions with the minimum-node recurrence and a consistent height convention.
Stack and Queue Implementation in Java: Arrays, Linked Lists, and the Interview Problems That Use Them
Implement stacks and circular queues in Java, trace every pointer through wrap-around, and choose the right standard collection for real code.
Sorting and Searching in Python: When to Implement the Classics and When to Use sort() and bisect
Learn when to write sorting and searching algorithms yourself, when Python's built-ins are the better choice, and how to explain the complexity of both.
How the MERN Stack Fits Together: One Request Traced from a React Click to MongoDB and Back
Follow one Enroll action through React, HTTP, Express, Mongoose, and MongoDB, then trace the JSON response back to the browser and its updated state.
Linked Lists and Trees in Python from Scratch: Node Classes, Traversals, and Interview Problems
Build linked lists and binary search trees with plain Python objects, then trace reversal, insertion, and traversal patterns that interviews repeatedly test.
Binary Tree Problems in Java: Traversals, Height, and the One Recursive Template Interviews Keep Testing
Learn one Java recursion pattern for binary-tree traversals, height, node counting, and diameter. Every result is worked on the same six-node tree.
Python for GATE DA: Programming and Data Structures, the Output Questions to Master
Build the Python mental model that GATE DA output and complexity questions demand, with a complete aliasing trace, a structure-cost table and safe rules for common traps.
HashMap Internal Working in Java: Hashing, Buckets, Treeification and the Interview Answer
Build the interview answer in four layers: index calculation, collision handling, resizing and treeification. Then test it against a mutable-key failure.
Python Data Structures: Lists, Tuples, Sets, Dictionaries
Choose among Python's four core containers by the operation you need most. See costs, hashability rules, a decision table and crisp interview answers.
Java Collections Framework Explained: ArrayList, HashMap and TreeMap
Choose Java collections by their contract and operation cost. What ArrayList, LinkedList, HashSet, HashMap and TreeMap each guarantee, what each costs, and how to say so in an interview.
Minimum Spanning Tree for GATE: Kruskal and Prim Numericals with Unique-MST Questions
Run Kruskal and Prim on the same weighted graph, verify their common cost, and use cut, cycle, and equal-weight reasoning to answer uniqueness questions.
Construct a Binary Tree from Traversals
Use inorder splits and preorder roots to rebuild a binary tree, then learn the BST shortcut and the cases where traversal data is not unique.