134. OCR A Level (H446) SLR23 – 2.2 Recursion

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About this video

OCR Specification Reference
A Level 2.2.1b

A recursive subroutine is one which calls itself. We take a look at the concept of recursion with the aid of some coded examples.

Key questions:

- What is recursion?
- When might you want to use recursion over iteration?

00:00 Recursion
00:09 Intro
00:14 A note about these videos
00:59 What is recursion?
01:49 Factorial
02:27 A program to calculate n! - Iteration
04:43 A program to calculate n! - Recursion
16:09 Iteration vs recursion
17:43 Key questions
17:55 Outro

Last updated: 24.07.26

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• SLR 23 – Programming techniques