13. Code: DFS

Depth First Search Intro

Tree 101 DFS Intro

Code Along with the Videos

Please open the notebook in a separate tab and follow along with the videos below. To open the notebook in a separate tab, right-click on the "jupyter" icon in the top left corner of the notebook and choose "open link in new tab."

Workspace

This section contains either a workspace (it can be a Jupyter Notebook workspace or an online code editor work space, etc.) and it cannot be automatically downloaded to be generated here. Please access the classroom with your account and manually download the workspace to your local machine. Note that for some courses, Udacity upload the workspace files onto https://github.com/udacity, so you may be able to download them there.

Workspace Information:

  • Default file path:
  • Workspace type: jupyter
  • Opened files (when workspace is loaded): n/a

Tree Setup

Tree 102 DFS Tree Setup

DFS uses a Stack

Tree 103 DFS Stack

Coding Step by Step

Tree 104 DFS Code Without A Loop

DFS implementation with a Bug

Let's look at a common error, an infinite loop, and explain why this is happening.

Tree 105 DFS Pre Order With Infinite Loop

Tracking Additional Information in the Stack

Tree 106 DFS Track State

Code that tracks the State in the Stack

Tree 107 DFS Track State Code

Pre-Order DFS with Recursion Code Intro

Tree 108 DFS Recursion Pre Order Intro

DFS Pre-Order with Recursion Solution

Tree 109 DFS Recursion Pre Order Solution

In-Order and Post-Order Code Intro

Tree 110 DFS Recursion In Order Post Order Intro

In-Order and Post-Order Solution

Tree 111 DFS Recursion In Order Post Order Solution

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