Assignment 2: Learn to C
Due Friday, September 12th, before midnight
The goals for this assignment are:
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Work with strings
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Work with structs
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Work with arrays
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Work with malloc/free
Update your repository
We will use the same repository as Assignment 1
First, you must accept the pull requst on your repository on Github (screenshot).
$ cd cs223-f25-classwork
$ git pullYour repository should now contain a new folder named A02.
1. Snackbar
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Due at end of lab **
Write a program, snackbar.c, that maintains a list of snacks available for purchase.
$ make snackbar
gcc snackbar.c -o snackbar
$ ./snackbar
Welcome to Steven Struct's Snack Bar.
How much money do you have? 5
0) Coco Puffs cost: $1.50 quantity: 4
1) Manchego cheese cost: $15.50 quantity: 6
2) Magic beans cost: $0.50 quantity: 0
What snack would you like to buy? [0,1,2] 1
You can't afford it!
$ ./snackbar
Welcome to Steven Struct's Snack Bar.
How much money do you have? 5
0) Coco Puffs cost: $1.50 quantity: 4
1) Manchego cheese cost: $15.50 quantity: 6
2) Magic beans cost: $0.50 quantity: 0
What snack would you like to buy? [0,1,2] 2
Sorry, we are out of Magic beans
$ ./snackbar
Welcome to Steven Struct's Snack Bar.
How much money do you have? 5
0) Coco Puffs cost: $1.50 quantity: 4
1) Manchego cheese cost: $15.50 quantity: 6
2) Magic beans cost: $0.50 quantity: 0
What snack would you like to buy? [0,1,2] 0
You bought Coco Puffs
You have $3.50 leftRequirements:
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Your program should define a
struct snackthat stores a name, cost, and quantity -
Your program should define at least three snacks and store them in an array
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Your program should be similar to the given output but feel free to customize it!
2. Dynamic snackbar
Implement a program, dynamic_snackbar.c, that allows users to add snacks to the snackbar.
Unlike last week’s snackbar, your program only needs two features:
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The ability to add a new snack to the list of snacks
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The ability to print out the current list of snacks
$ make dynamic_snackbar
gcc dynamic_snackbar.c -o dynamic_snackbar
$ ./dynamic_snackbar
Enter a number of snacks: 3
Enter a name: Slurm
Enter a cost: 1.50
Enter a quantity: 3
Enter a name: Beans
Enter a cost: 5
Enter a quantity: 1
Enter a name: Carrots
Enter a cost: 2
Enter a quantity: 10
Welcome to Dynamic Donna's Snack Bar.
0) Slurm cost: $1.50 quantity: 3
1) Beans cost: $5.00 quantity: 1
2) Carrots cost: $2.00 quantity: 10Requirements/Hints:
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You must use malloc to create an array large enough to hold all the snacks
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Use scanf to get the number of snacks and their attributes
| You do not need to type in the attributes every time. You can put the inputs in a file and then use redirection to load it. |
3. Shift Cypher
Write a program, cypher.c, that asks the user for a word and then encodes it
using a shift cypher. A shift cypher replaces each letter with a letter that is
X positions from it in the alphabet. For example, is the letter is 'a' and the
shift is 2, we replace 'a' with a 'c'. You can assume that all inputs are
lowercase and do not contain special characters.
$ make cypher
gcc cypher.c -o cypher
$ ./cypher
Enter a word: elephant
Enter a shift: 2
Your cypher is gngrjcpv
$ ./cypher
Enter a word: gngrjcpv
Enter a shift: -2
Your cypher is elephant
$ ./cypher
Enter a word: hello
Enter a shift: 7
Your cypher is olssv
$ ./cypher
Enter a word: a
Enter a shift: -2
Your cypher is y
$ ./cypher
Enter a word: z
Enter a shift: 2**
Your cypher is bHints:
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Recall that characters as represented as digits in ASCII. A straight-forward implementation can add offsets to each character of the word.
4. Minesweeper
Implement a program, minesweeper.c, that generates a minesweeper board.
In Minesweeper, each cell can either
contain a bomb or not. Cells without bombs are called safe cells.
Your program should take three command line arguments — m, n, and p — and generate a m x n grid of cells where each cell has probability p of containing a bomb. Then, you program shoul print out the grid using X for bombs and . (period) for safe cells. Finally, your program should output an additional 2D grid with the number of neighboring bombs for each cell (above, below, left, right, NW, NE, SW, SE).
$ make minesweeper
gcc -g -Wall -Wvla -Werror minesweeper.c -o minesweeper
$ ./minesweeper 3 5 0.4
X X . . .
. . . . .
. X . . .
X X 1 0 0
3 3 2 0 0
1 X 1 0 0Requirements/Hints:
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Use malloc and free to allocate a 2D array to store the grid.
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Use rand() and srand(time(0)) to create random boards
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Your program must use command line arguments!
To read in command line arguments, define main with argc and argv parameters
as follows. The first command line argument is always the program name. argc is
the number of arguments. You can use atoi and atof to convert from strings
to numeric types (int and float respectively)
|
int main(int argc, char** argv) {
if (argc != 4) {
printf("usage: %s m n p\n", argv[0]);
}
return 0;
}Submit your Work
Push you work to Github to submit your work.
$ cd A02
$ git add *.c
$ git commit -m "A02 complete"
$ git pushGrading Rubric
Assignment rubrics
Grades are out of 4 points.
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(1 point) minesweeper
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(0.1 points) style
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(0.4 points) correct behavior: asks the user for input and creates the new string
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(0.5 points) no memory errors
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(1 point) cypher
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(0.1 points) style
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(0.4 points) correct behavior: asks the user for input and creates the new string
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(0.5 points) no memory errors
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(1 points) snackbar
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(0.1 points) style
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(0.4 points) correct behavior
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(0.5 points) no memory errors
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(1 points) dynamic_snackbar
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(0.1 points) style
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(0.4 points) correct behavior
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(0.5 points) no memory errors
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Code rubrics
For full credit, your C programs must be feature-complete, robust (e.g. run without memory errors or crashing) and have good style.
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Some credit lost for missing features or bugs, depending on severity of error
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-12.5% for style errors. See the class coding style here.
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-50% for memory errors
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-100% for failure to checkin work to Github
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-100% for failure to compile on linux using make