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Track 08 of 10
Data StructuresIntermediate Level~25 Mins
8. Singly & Doubly Linked Lists
Understand node pointers, head references, traversal, insertion, and list reversal.
The "WHY" Core Principle
Arrays require contiguous memory blocks. Linked lists store disconnected Node objects on the Heap.
Interactive Visualizer
Stack (LIFO) & Queue (FIFO) Interactive Simulator
Observe the difference between Last-In First-Out (Stack) and First-In First-Out (Queue).
val: 10
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val: 30TOP
Interactive Code Snippets (1 Lessons)
Lesson 01
Reverse a Singly Linked List In-Place
O(N)O(1)
Reverse all node `.next` pointers in O(N) time and O(1) auxiliary space.
WHY Under The Hood:
Maintain three pointers: `prev`, `curr`, and `next_node`. Update `curr.next = prev` at each step.
CPython C Struct Detail: Reversing pointers modifies PyObject reference attributes in place.
Reverse a Singly Linked List In-Place
Pyodide WASM EngineType, edit code, and click 'Run & Profile' to see live runtime ms and operation count!
Python 3.12 Code (Editable)
Expected:Time: O(N)Space: O(1)