PJ017: Debug The List Changes And Find The Max

This project is used to build basic concept of list, get familiar of basic operations of list, and use for-looping to access the stored elements values. This is a knowledge base for further projects using lists and looping. Goals:

Basic operation of lists, add and remove element
Use count-controlled for-looping to access list elements
A basic debugging experience to watch the lists changes and looping

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Result Demo

Here is the demo of the basic requirement, and a short introduction of how to debug.

PJ017_Debug_The_List_Changes_And_Find_The_Max.mp4

Knowledge Preparations

Test the Demo of List Operations

Inspect the List Changes in Debugger

Task: Find the Max Value

Task: Check Duplications Before Adding

Discussion & Sharing

The Working Copy

Referred/Used By

Requirement

Hardware setup

This project uses 1 Micro:bit board with a USB cable, nothing else needed.

Programming

The basic part of the program is ready-made and provided to the student to directly inspect and debug
- A list created on-start, with default 3 number-elements
- Press button-A to add a random number (within 0-9) to the end of the list, show this number on LED screen
- Press button-B to pop-up the last number from the list
- Press LOGO to read and show the stored numbers
Task 1: When pressing A+B, find the max value from the list, then show it
Task 2: Improved logic for button A: Check values duplication, warn a sound, don't add duplicated new values

Effort Estimation

[x] Simple: 30-60 minutes

[ ] Moderate: 1-2 hours

[ ] Challenging: more than 2 hours

The estimation bases on average situation without unexpected troubleshooting, assuming that the student meets prerequisites. It only indicates rough time needed to complete this project, but not about technical difficulty, not covering discussion and sharing time. Here is a possible breakdown:

5 minutes: Understand requirement and solution, collect materials
15-20 minutes: Use debugger to inspect how the things happen and the changes of list length, index, values
10-15 minutes: Task 1, find the max num
10-15 minutes: Task 2: check duplication

Prerequisite

One should have prior knowledge

Micro:bit V2 board: Know what they are, better to have prior experience with it
MakeCode by Microsoft, the programming tool, better to have prior experience using it with Micro:bit
KB015: List Basic Concept

Tools & Materials

A laoptop or tablet with internet access
1x Micro:bit V2 board , with USB cable

Knowledge Preparations

Basic Concept and Operations

List v.s. Array
Index
Elements/Objects/Values

KB015: List Basic Concept

Test the Demo of List Operations

Copy the code as the picture, or directly get a copy from MakeCode shared project: PJ017: Debug The List Changes And Find The Max - Demo Debug Only.

Please read and understand the logic, then download to Micro:bit to test.

Inspect the List Changes in Debugger

Follow the tutor to learn how to start debug, and watch the changes of list.

Then, please repeat and explore the debugging by yourself.

Task: Find the Max Value

Requirement

When pressing button A+B

Find the max value from the list
Show this number on LED screen

The purpose of this task is to practice using for-looping to access elements in the list.

Tips

There are many ways to do so, one of the solutions:

Create a variable "max_value"
Let "max_value" be any value from the list
Go through all the values from the list, compare with max_value, update it to be the value that is bigger than it was

Working copy

Here is a working copy, if you need...

Task: Check Duplications Before Adding

Requirement

When pressing button A

Check if the new random number already exists in the list
If yes, then warn a sound, and don't add it into the list

The purpose of this task is to practice using for-looping to access elements in the list.

Tips

There are many ways to do so, one of the solutions:

Go through all the values from the list using for-looping, compare with the new generate number, if yes, then a duplication is found
Use "break" to jump out of the looping when it's found already

No lazy working copy here, please solve it.

Discussion & Sharing

This optional part covers further competence development, in terms of testing, troubleshooting, analysis, documentation, flow chart diagrams practices, etc.

Presentation & Demo

Stand in front of the class, share with your group what you have made, please cover important points

Tell what it is your product
Demonstrate how it works
Explain how it works

Troubleshooting Stories

Share with your group about

What troubles you met
How you analyze
How you get help
How you solve it
What you have learnt

The Working Copy

Find out working copy as a MakeCode shared project.

Referred/Used By

Used by LP2445: List, Looping and Debugging, 24w45