Main Navigation Home Roadmap Patterns Data Structures Practice

Part III — Data Structures in Depth

Overview

Arrays

Rotate Image (90° clockwise, in place)

Spiral Matrix (layer-by-layer traversal)

Set Matrix Zeroes (use row 0 / col 0 as markers)

Find the Missing Number

Find All Missing / All Duplicate Numbers

First Missing Positive (Hard)

Strings

Longest Palindromic Substring (Expand Around Center)

Encode and Decode Strings (Length Prefixing)

Linked Lists

Reverse a Linked List

Reorder / Palindrome via Split-Reverse-Merge

LRU Cache (Design)

Stacks & Queues

Valid Parentheses

Min Stack (O(1) minimum)

Trees

Maximum Depth, Balanced, Diameter (post-order aggregation)

Lowest Common Ancestor

Validate BST & BST operations

Serialize / Deserialize (structure encoding)

Construct Tree from Traversals

Tree DP (House Robber III)

Heaps

Find Median from Data Stream (Two Heaps)

Trie

Implement Trie

Graphs

Number of Islands (grid flood fill)

Rotting Oranges (multi-source BFS)

Dijkstra (weighted shortest path, non-negative)

Bellman–Ford (negative edges & negative-cycle detection)

Clone Graph & Bipartite (traversal bookkeeping)

Bridges & Articulation Points (Tarjan) — Critical Connections

Eulerian Path (Hierholzer) — Reconstruct Itinerary

Segment / Fenwick Tree

Fenwick Tree (Binary Indexed Tree)

Segment Tree (range query + range update)

On this page

Home›
Data Structures

Data Structures in Depth

Select a section from the sidebar to begin.

Pager

Next pageArrays

Released under MIT license.

💡 Quick shortcuts

H HintsR Run JavaA AI Help

Data Structures in Depth ​

Data Structures in Depth