Chapter 23 // Exercises 15 , 16- Principles & Practice Using C++

In this exercise I am using Visual Studio 2019 and a modified version of the std_lib_facilities header found here.

Chapter 23 // Exercise 15

Describe a pattern that cannot be expressed as a regular expression.

HTML.

Chapter 23 // Exercise 16

For experts only: Prove that the pattern found in the previous exercise really isn't a regular expression.

https://stackoverflow.com/questions/1732348/regex-match-open-tags-except-xhtml-self-contained-tags