Master Doubly Linked List - Interactive Learning
Doubly Linked List - DSA Learning Platform 🔗 Doubly Linked List Bidirectional traversal with prev and next pointers - Memory Address Visualization 📚 Interactive Tutorial Learn doubly linked lists step-by-step with hands-on examples Step 1: Understanding Doubly Linked Nodes Each node in a doubly linked list contains three parts: PREV: Memory address of the previous node (or NULL) DATA: The actual value stored NEXT: Memory address of the next node (or NULL) See Node Structure → Step 2: Bidirectional Links Unlike singly linked lists, we can traverse both directions: Forward: Follow NEXT pointers (HEAD → TAIL) Backward: Follow PREV pointers (TAIL → HEAD) Watch Bidirectional Traversal → Step 3: Easy Deletion With PREV pointer, deletion is simpler - no need to track previous node separately! See Deletion Advantage → Step 4: HEAD and TAIL Pointers Maintaining both HEAD and TAIL allows O(1) insertion/deletion at both ends. Compare Operations → 💡 Learning Examples 🔄 Reverse Traversal See how PREV pointers enable backward traversal from TAIL to HEAD. Run Example 📍 Insert in Middle Watch how insertion updates both PREV and NEXT pointers. Run Example 🗑️ Delete Any Node See how PREV pointer makes deletion easier than singly linked list. Run Example 🔀 Palindrome Check Use bidirectional traversal to check if list is palindrome. Run Example ⚙️ Operations 📥 Insert at Head (O(1)) Insert at Head 📤 Insert at Tail (O(1)) Insert at Tail 📍 Insert at Position Insert at Position 🗑️ Delete Operations Delete by Value Delete Head Delete Tail 🔍 Search Node Search 🎬 Traverse ▶ Forward (HEAD→TAIL) ◀ Backward (TAIL→HEAD) ⚡ Quick Actions Load Sample List 🗑️ Clear All 💡 DLL Advantage • Traverse in both directions • O(1) delete at tail • No need to track previous node during deletion 🔍 Doubly Linked List Visualization PREV Pointer DATA NEXT Pointer → Forward Link ← Backward Link Size: 0 nodes | HEAD: NULL | TAIL: NULL 📋 Status: Add nodes to build the doubly linked list. Watch how PREV and NEXT pointers connect nodes! Insert Head O(1) Insert Tail O(1) Delete Head O(1) Delete Tail O(1) Search O(n) 📍 Memory Layout (Doubly Linked) Address Data ← Prev Next → No nodes in memory 🌍 Real-World Applications: Browser History: Navigate back and forward between pages Music Players: Previous/Next song functionality Undo/Redo: Text editors, image editors navigation LRU Cache: Least Recently Used cache implementation Deque: Double-ended queue implementation ⚖️ Doubly vs Singly Linked List: Memory: DLL uses more memory (extra PREV pointer) Traversal: DLL can traverse both directions Delete Tail: DLL is O(1), SLL is O(n) Deletion: DLL doesn't need previous node reference Complexity: DLL has more pointer updates on insert/delete ⚠️ Common Mistakes to Avoid: Forgetting PREV: Always update both PREV and NEXT pointers Edge Cases: Handle empty list and single node cases NULL Checks: Check for NULL before accessing node->prev or node->next Update Order: Update new node's pointers before...
Subject: Data Structures with Animation | Chapter: Doubly Linked List