Conversion of Regex to DFA Directly with Brzozowski Derivatives

Here we show, with an example, that one can create a DFA directly from a regular expression using Brzozowski Derivatives. Therefore, no NFA is ever needed to do the conversion. We first set the start state to be the original regex, and its transitions correspond to taking partial derivatives of that regex with each of the input characters. If a new regex is formed that hasn't been seen before, then that transition goes to a new state. This is repeated until no new states are formed, and the final states are ones that can make the empty string (epsilon). The original video is here:    • Brzozowski Derivatives (aka WTF is a regex...   #easytheory #gate #theory Contribute: Donation (appears on streams): https://streamlabs.com/easytheory1/tip Paypal: https://paypal.me/easytheory Patreon:   / easytheory   Discord:   / discord   Youtube Live Streaming (Sundays) - subscribe for when these occur. Social Media: Facebook Page:   / easytheory   Facebook group:   / easytheory   Twitter:   / easytheory   Merch: Language Hierarchy Apparel: https://teespring.com/language-hierar... Pumping Lemma Apparel: https://teespring.com/pumping-lemma-f... If you like this content, please consider subscribing to my channel:    / @easytheory   Gold Supporters: Micah Wood Silver Supporters: Timmy Gy ▶SEND ME THEORY QUESTIONS◀ [email protected] ▶ABOUT ME◀ I am a professor of Computer Science, and am passionate about CS theory. I have taught many courses at several different universities, including several sections of undergraduate and graduate theory-level classes.