160. OCR A Level (H446) SLR26 – 2.3 Measures and methods to determine efficiency of algorithms
About this video
OCR Specification Reference
A Level 2.3.1c
This video takes a look at the various measures and methods you can use to determine the efficiency of different algorithms. It discusses these concepts in terms of the following Big O notations: Constant, Linear, Polynomial, Exponential and Logarithmic complexity.
Key questions:
- What is Big O notation and how can we use it to help classify the complexity of algorithms?
- What are constant, logarithmic, linear, polynomial and exponential complexity?
00:00 Measures and methods to determine efficiency of algorithms
00:12 Intro
00:17 Algorithm complexity
02:36 Time and space complexity
03:13 Algorithm complexity - Part 2
04:17 Big O notation rules
04:52 Algorithm complexity - Part 3
05:38 Recap
06:09 Big O notation classifications
07:06 O(1) - Constant complexity
07:24 O(log n) - Logarithmic complexity
07:47 O(n) - Linear complexity
08:17 O(n^2) - Polynomial complexity
09:19 O(2^n) Exponential complexity
09:57 Big O notation
10:21 Multiple functions being performed on input
12:23 Quick tips for working out Big O notation time complexity
13:26 Key questions
13:46 Big O notation cheat sheet
14:41 Outro
Last updated: 28.07.26
