Recursive functions

To understand recursion, you must first understand recursion.

You may think of recursion as a programming structure where a function calls itself. We call such a function a recursive function. Many algorithms can be implemented using recursion. Here’s a brief introduction to recursion and recursive functions.

See also: Essential Algorithms, chapter 9 (Recursion, Basic Algorithms) for more on recursion, factorial, and Fibonacci.

Further reading

• https://plato.stanford.edu/entries/recursive-functions/ (Stamford Encyclopedia of Philosophy)
• https://en.wikipedia.org/wiki/Recursion_(computer_science) (Wikipedia)
• Hofstadter, Douglas R., Gödel, Escher, Bach : An Eternal Golden Braid. New York, Basic Books, 1979.
  • See Chapter V. Recursive Structures and Processes. Note that this chapter also discusses stacks, pushing, and popping, which we’ll see a little later in the course.

Resources

• Recursive_Functions.pdf

Comprehension check

1. Every recursive function must have at least one ___________ case and at least one ___________ case.
2. Is recursion always the most efficient way to solve a problem?
3. Without a __________________ recursion can lead to infinite regress.

Answers: ǝsɐɔ ǝsɐq / ou / ǝʌᴉsɹnɔǝɹ ’ǝsɐq

Amusement

Visit: https://thomaspark.co/2017/01/relevant-xkcd/

Gru’s plan, https://imgflip.com/memegenerator/Grus-Plan, with mods

Original author: Clayton Cafiero < [given name] DOT [surname] AT uvm DOT edu >

No generative AI was used in producing this material. This was written the old-fashioned way.

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