How to Not Swear with Regular Languages - Easy Theory

Опубликовано: 07 Август 2026
на канале: Easy Theory
375
20

Here we show how to not swear or say "bad words", with a regular expression and a DFA. By this, we mean all strings over {a, b, c, d} that avoid a particular substring abcd. Feel free to substitute your favorite 4-letter swear word!

Timeline:
0:00 - Regex for Not Swearing
5:53 - DFA for Not Swearing

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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.