Breadth First Search VS. Depth First Search (with Pictures!)

An illustrated introduction to BFS and DFS through an undirected graph (no prior knowledge necessary).

Photo by Fletcher Pride on Unsplash

Breadth First Search and Depth First Search are basic search algorithms that represent a simple method to solve a problem. They are a precursor to modern types of search and in my opinion a must know building block for learning artificial intelligence.

If learning artificial intelligence is your overall goal I recommend checking out this great post by Daniel Bourke:

My Self-Created Artificial Intelligence Masters Degree

Background

Undirected vs Directed Graph

To be completely honest I was confused when I first heard the terms “undirected graph” and “directed graph”. Before we get into the meat of this article let me clarify:

Image by author, illustration by author.