Explaining Algorithms (Cambridge (CIE) O Level Computer Science)

Explaining Algorithms

How do you explain an algorithm?

• A well designed algorithm should be able to be interpreted by a new user and they should be able to explain what it does

• Algorithms can be written using flowcharts, pseudocode or high-level programming language code such as Python

• The purpose of an algorithm is to solve a problem, if a user does not know the goal of the algorithm, then following the algorithm instructions should make its purpose clear

• If the algorithm is complex then additional ways to understand the problem could be:

  • Look for comments in the code

  • Consider the context of where the algorithm is being used

  • Test the algorithm with different inputs

• Look at the following algorithm, can you explain what it does?

• The purpose of the algorithm is to add ten user-entered numbers together and output the total

• The processes are: 

  • initializing three variables (Count, Number, Total)

  • inputting a user number

  • adding to two variables (Total, Count) 

  • repeating nine more times

  • outputting the final Total value