Hello,
these are code proposals to be done with App Inventor BLOCKS.
Please do not publish the answers in this discussion, since they are proposals for users who want to try or teachers who want to propose to their students.
1.- 6x6 button matrix.
2.- Change the color of midword.
Read this... https://bionic-reading.com/br-method/
Create an application that modifies the color of the words in a text.
The first half of the letters of each word must be in red and the other half in black.
If the word has an odd number of letters, the first half plus the next letter should be in red, example:
range
range
Use Label - HTMLFormat
3.- Chess knight moves.
CaballoAjedrez_Community.aia (5.6 KB) (unfinished)
4.- Sum of domino pieces.
Each time the button is pressed, 3 horizontal dominoes must be displayed randomly (they can be repeated).
A bottom label should show the sum of the left and right side of the pieces.
UNICODE characters (🀯 - 🁡) must be used to draw the pieces. Use Label with HTMLFormat propertie.
https://www.mclibre.org/consultar/htmlcss/html/html-unicode-simbolos.html#gr-domino
To place the pieces correctly use a Canvas.
5.- Variations with repetition.
We have the following elements: 'abcdefghijklmnopqrstuvwxyz .'
Make an app that displays each of its variations in a list.
Note that they are: "aa",...,"a ",..,"ab",...,"ba"
Check: https://www.hackmath.net/en/calculator/combinations-and-permutations?n=28&k=2&order=1&repeat=1
const elements = 'abcdefghijklmnopqrstuvwxyz .';
const n = elements.length;
const variations = [];
for (let i = 0; i < n; i++) {
for (let j = 0; j < n; j++) {
variations.push(elements[i] + elements[j]);
}
}
AppInventor.setWebViewString("" + variations);
6.- Two-letter index in the variations list.
th..... 540
e ..... 139
li...... 317
on.... 406
7.- Text to Egyptian hieroglyphics.
th..... 540
e ..... 139
li...... 317
on.... 406
Note: this is just a programming exercise, the obtained hieroglyph has no relation to the written text.
If you want to learn a little about hieroglyphics, use Fabricius from Google.
8.- Create an application to solve the wolf, goat and cabbage problem.
A farmer went to a market and purchased a wolf, a goat, and a cabbage. On his way home, the farmer came to the bank of a river and rented a boat. But crossing the river by boat, the farmer could carry only himself and a single one of his purchases: the wolf, the goat, or the cabbage. from Wikipedia.
https://en.wikipedia.org/wiki/Wolf,_goat_and_cabbage_problem
https://upload.wikimedia.org/wikipedia/commons/c/c6/Playable_Fox_Chook_Corn_puzzle.svg
9.- Automatic Knight's tour.
In "3.- Chess knight moves" we saw the possible places where the Knight can be placed.
Make an app where the user clicks on any Button (for example the b38) and automatically, every second, change the position of the knight to any (random) of the correct positions, until no more correct movements are possible. The Knight should not repeat position.
Consultation:
https://en.wikipedia.org/wiki/Knight%27s_tour
How many directed closed tours can there be on an 8x8 board?
Why is Euler's square said to be semimagic?
10.- Travelling salesman problem (TSP).
Given a set of cities and the distance between every pair of cities, the problem is to find the shortest possible route that visits every city exactly once and returns to the starting point. from https://www.geeksforgeeks.org/travelling-salesman-problem-using-dynamic-programming/
Vendedor.aia (75.3 KB) (unfinished)
10B.- Now with 5 cities.
11.- Toothed wheels.
p91J_RuedasDentadas_i.aia (99.8 KB) (unfinished)
12.- Game Ball falls.
You can improve the game with these ideas...
https://iamkun.github.io/tower_game/?s=1682244761607?s=1682247555106?s=1682249232908?s=1682249273101
13.- Morse with colors.
When it emits a dot, the screen flashes White - Green
When it emits a dash, the screen flashes Black - Green
When a letter ends, the screen turns Red.
https://theorycircuit.com/color-sensor-tcs3200-arduino-interfacing/
14.- Color mixing.
There are two important ways to mix colors: additive mixing and subtractive mixing.
The additive mixing uses as primary colors: Red, Green and Blue (RGB), it is used in lights, monitors, projectors, light bulbs, television...
The subtractive mixing of colors uses as primary colors: Cyan, Magenta and Yellow (CMY), it is used in pigments, paints, printers,...
https://en.wikipedia.org/wiki/Color_mixing
