Pseudocode example
The programmer will consider the purpose and functional requirements that were established at the analysis phase.
In this example, the information from the analysis phase is shown to provide a context for the pseudocode examples that follow.
Analysis used to inform design
Purpose
- A program is to be developed to create usernames for a class of twenty pupils
- The program will ask a teacher to enter the first name, surname and age of each pupil.
- The age entered must be between five and eighteen.
- The program should output a list of usernames for the teacher.
Functional requirements
| Inputs | Processes | Outputs |
| Pupil first name | Validate age | List of usernames |
| Pupil surname | Create username | |
| Pupil age |
| Inputs | Pupil first name |
|---|---|
| Processes | Validate age |
| Outputs | List of usernames |
| Inputs | Pupil surname |
|---|---|
| Processes | Create username |
| Outputs |
| Inputs | Pupil age |
|---|---|
| Processes | |
| Outputs |
Design using pseudocode
Main steps (algorithim)
1 Initialise username
2 Start fixed loop for twenty pupils
3 聽 聽 聽 聽 Get first name and surname from user
4 聽 聽 聽 聽 Get valid age from user
5 聽 聽 聽 聽 Generate username
6 Display "Username", index, "is" username
7 End fixed loop
Refinement
3.1 Get first name and store in first name array
3.2 Get surname and store in surname array
4.1 Get age and store in age array
4.2 While age is less than 5 or higher than 18 start conditional loop
4.3 聽 聽 聽 聽 Display error message "Invalid age, enter a number between 5 and 18 inclusive"
4.4 聽 聽 聽 聽 Get age and store in age array
4.5 End conditional loop
5.1 Concatenate first name, surname and age and store in username array
5.2 Start fixed loop from 0 to index -1
5.3 聽 聽 聽If username equals stored username
5.4 聽 聽 聽 聽 聽 Add 1 to age
5.5 聽 聽 聽 聽 聽 Concatenate first name, surname and age and store in username array
5.6 聽 聽 聽 聽End If
5.7 End fixed loop
In the above example, the algorithm is designed in such a way that if a pupil has the same username as one already stored, the code will add one to their age and attempt to store the username again. The loop will repeat until the username generated is unique.