Description
Arrays and Swap
Provided Files
● main.c
● myLib.c
● myLib.h
● cat.c
● cat.h
Files to Edit/Add
● main.c
● cat.c
● Makefile
● .vscode
○ tasks.json
Instructions
In this lab, you’ll be writing code to swap cat structs. Note: Make sure to copy over your
Makefile and .vscode/tasks.json from one of your previous assignments.
TODO 1.0
● In cat.c, initialize the catBitmaps array. The array should contain the already
defined bitmaps: bitmap1, bitmap2, bitmap3, bitmap4, and bitmap5.
TODO 2.0
● In cat.c, complete the switch statement. In this switch statement, we are setting
pixels a particular color based on the retrieved value from the cat bitmap. Each cat
bitmap has 6 possible values, 0, 1, 2, 3, 4, or 5. Create a case for values 1, 2, 3, 4, and
5. The 0 case can be handled by the default statement, as we will not set the pixel
any color if the value of the bitmap is 0.
○ For case 1, set the color of the pixel at col + i, row + j to WHITE.
■ WHITE a macro defined for you in myLib.h.
○ For case 2, set the color of the pixel to MAGENTA.
■ MAGENTA is a macro defined for you in myLib.h. ○ For case 3, set the color of the pixel to GREY.
■ GREY is a macro defined for you in myLib.h.
○ For case 4, set the color of the pixel to the cat’s furColor.
■ Make use of the cat pointer that is passed into the function, and access
that cat struct’s furColor member.
○ For case 5, set the color of the pixel to LIGHTGREY.
■ LIGHTGREY is a macro defined for you in myLib.h.
● Build and run your lab thus far. You should see the following. If you do not, fix your
code before moving forward.
TODO 3.0-3.2
This requires several moving parts, so it is broken into three parts.
● TODO 3.0
○ At the bottom of main.c, write a function called swap that swaps two cat
structs. Refer to lecture material to get a refresher on how to implement
swap if needed.
● TODO 3.1
○ At the top of main.c, add the function prototype for the swap method you
just wrote.
● TODO 3.2
○ In main.c, implement the reverseCats function. To do this, you will
write an in-place array reversal for the cats array. “In-place” means that
you may not use an additional array or data structure to reverse the contents
of the array. Thus, you will need to call the swap method you wrote to
perform the in-place array reversal.
■ Hint: you only need to iterate through half of the array to swap the
elements!
■ Hint: there’s no array.length method in C! Make use of the
CATSCOUNT macro in cat.h instead.
● Build and run your lab. When you press START, you should see that the cats have
reversed their order. You can press START again to see that the cats have returned
to their original positions.
○ The images that follow show what you should see (1) before you’ve reversed
your cats and (2) after you’ve reversed your cats. If you see (1), then (2) after
pressing START, you’ve completed the lab correctly. Otherwise, fix your code
before moving forward.
(1)
(2)
You will know if it runs correctly if you can:
● Press START to see the cats reversed
Tips
● Review lecture materials for how to implement swap.
● Draw out what your logic for reverseCats actually does. This will help you
ensure you’ve implemented the code correctly!
● Follow each TODO in order, and only move forward if everything is correct
Submission Instructions
Zip up your entire project folder, including all source files, the Makefile, and everything
produced during compilation (including the .gba file). Submit this zip on Canvas. Name
your submission Lab03_FirstameLastname, for example: “Lab03_KittyKat.zip”.
