Data Structure & Algorithm 📚

A comprehensive collection of Data Structures and Algorithms implemented in C++. This repository serves as a learning resource and reference guide for fundamental computer science concepts.

🎯 Overview

This repository contains implementations of various data structures and algorithms in C++. Each topic is organized in its own directory with well-documented code examples and implementations.

📊 Detailed Breakdown

🔹 Data Structures (Core)

Folder	Description	Key Implementations	Complexity
Array	Linear data structure with contiguous memory allocation	Basic operations, searching, sorting, rotation	Access: O(1)
Linked_List	Dynamic linear data structure with nodes connected via pointers	Singly, Doubly, Circular variants	Insertion: O(1)
Stack	LIFO (Last In First Out) data structure	Push, Pop, Peek, Expression evaluation	Operations: O(1)
Queue	FIFO (First In First Out) data structure	Enqueue, Dequeue, Circular Queue, Priority Queue	Operations: O(1)
Tree	Hierarchical non-linear data structure	Binary Tree, BST, AVL, Heap, Traversals	Search: O(log n)
Graph	Non-linear structure representing nodes and edges	BFS, DFS, Shortest Path, Spanning Tree	Varies by algorithm
String	Sequence of characters	Pattern matching, manipulation, searching	Varies by operation

🔹 Algorithms

Category	Algorithms Included	Time Complexity
Searching	Linear Search, Binary Search	O(n), O(log n)
Sorting	Bubble, Selection, Insertion, Merge, Quick, Heap Sort	O(n²) to O(n log n)
Graph Traversal	BFS, DFS	O(V + E)
Shortest Path	Dijkstra's, Bellman-Ford	O(V²), O(VE)

🔹 Problem-Solving Patterns

Pattern	Use Cases	Example Problems
Two Pointer	Array/String traversal, Pair problems	Container with Most Water, Remove Duplicates
Sliding Window	Subarray problems	Maximum Sum Subarray, Longest Substring
Fast-Slow Pointer	Cycle detection, Middle element	Detect Cycle in Linked List

🚀 Topics Covered

📦 Data Structures

• ✅ Arrays

  • Array operations (insertion, deletion, traversal)
  • Searching and sorting
  • Rotation problems
  • Subarray problems

• ✅ Linked Lists

  • Singly Linked List
  • Doubly Linked List
  • Circular Linked List
  • Reversal techniques
  • Cycle detection

• ✅ Stacks

  • Array-based implementation
  • Linked List-based implementation
  • Expression evaluation
  • Parentheses matching

• ✅ Queues

  • Simple Queue
  • Circular Queue
  • Priority Queue
  • Deque (Double-ended Queue)

• ✅ Trees

  • Binary Tree
  • Binary Search Tree (BST)
  • Tree traversals (Inorder, Preorder, Postorder, Level Order)
  • AVL Tree
  • Heap

• ✅ Graphs

  • Graph representations
  • BFS and DFS traversals
  • Shortest path algorithms
  • Minimum spanning tree

• ✅ Strings

  • String manipulation
  • Pattern matching (KMP, Rabin-Karp)
  • String reversal and rotation

🧮 Algorithms

• Searching: Linear Search, Binary Search
• Sorting: Bubble, Selection, Insertion, Merge, Quick, Heap Sort
• Graph Algorithms: BFS, DFS, Dijkstra's, Bellman-Ford
• Pattern Matching: KMP, Rabin-Karp
• Dynamic Programming: Coming soon
• Greedy Algorithms: Coming soon

🎯 DSA Patterns

• Two Pointer Technique
• Sliding Window
• Fast and Slow Pointers
• More patterns coming soon...

👨‍💻 Author

Soumen Sen
GitHub: @soumensen411