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Track 010 of 10
Data StructuresAdvanced Level~30 Mins

10. Graphs & Graph Traversals (BFS & DFS)

Explore network nodes, adjacency lists, Breadth-First Search (BFS), and Depth-First Search (DFS).

The "WHY" Core Principle

BFS explores neighbor nodes level-by-level using a FIFO Queue, guaranteeing shortest path discovery.

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
val: 20
val: 30TOP

Interactive Code Snippets (1 Lessons)

Lesson 01

Graph BFS Shortest Path Algorithm

O(V + E)O(V)

Traverse an unweighted graph level-by-level using BFS Queue.

WHY Under The Hood:

A `visited` set prevents infinitely looping in cyclic graphs.

CPython C Struct Detail: Graph Adjacency List is represented in Python as a dict mapping node keys to lists.

Graph BFS Shortest Path Algorithm

Pyodide WASM Engine

Type, edit code, and click 'Run & Profile' to see live runtime ms and operation count!

Python 3.12 Code (Editable)
Expected:Time: O(V + E)Space: O(V)

Test Your Understanding

WHY does Breadth-First Search (BFS) guarantee finding the shortest path in unweighted graphs?