CS 2110 Project 4: C Programming Solution

1 Introduction
Hello and welcome to Project 4. This project is separated into 2 parts. Part 1, consists of functions you have seen in project 3 but now you get to complete them in C! Part 2, you’ll write a calendar program in C!
2 Am I allowed to make my own functions?
Yes! You are allowed to make your own helper functions in the ’.c’ project files if you so desire.
3 Part 1 - Assembly Functions in C
For this first section you will be completing Project 3 again but this time you have the C language to help you out. This section is specifically designed to demonstrate the power of C.
3.1 Compare
You are given two parameters: ‘a‘ and ‘b‘. The value you return depends on whether ‘a‘ is greater than ‘b‘.
1. return -1 if b is larger
2. return 0 if equal
3. return 1 if a is larger
3.2 Modulus
Since there are different interpretations of modulus for negative numbers, you should take the absolute value of both of your parameters and then perform the operation. Return the result of the modulus operation.
3.3 String Manipulation
You will write a function that takes in a string stored in memory, changes any lowercase letters in the string to uppercase characters. Implement toUppercase.
* Strings are essentially a contiguous array of ASCII values. In this case, the first character is stored at theaddress given by the parameter ‘string‘.
* The string continues until the first instance of a null terminator, which has the value of 0.
* Memory addresses in C can be treated as arrays. In particular, writing ‘string[i]‘ will give the i-th characterin ‘string‘. You can read from that character, as well as assign to it.
Example:
string = x4000
---------------------------------------
| ’h’ | ’A’ | ’h’ | ’A’ | ’’ |
| x4000 | x4001 | x4002 | x4003 | x4004 |
---------------------------------------
The string that you receive can contain any characters, and you should change all letters to uppercase, and leave non-letters as is.
3.4 Shift Right
You will be given an original value, and an amount of bits to shift by to the right. Return the shifted value. You will not have to handle overflow.
3.5 Shift Left
You will be given an original value, and an amount of bits to shift by to the left. Return the shifted value. You will not have to handle overflow.
3.6 Collatz
You will be implementing a calculator for iterations of the Collatz Conjecture.
The Collatz Conjecture is a famous unsolved math problem, which operates under a few simple rules. We have our Collatz function, C(n), which takes in exclusively positive integers.
1. If n is an odd number, C(n) = 3n + 1
2. If n is an even number, C(n) = n/2
From here, we seek to calculate how many times we need to run n (and its subsequent results) through the Collatz function in order for it to reach the value 1.
3.7 Dot Product
The last method you will be writing is a dot product calculator. Given two arrays in memory, your job is to compute the dot product and return it back into memory. In mathematics, the dot product is calculated as the sum of multiplication between each pair of vector components.
If A = [ a1 a2 a3 ] and B = [ b1 b2 b3 ], then the dot product between A and B would be
(a1 ∗ b1) + (a2 ∗ b2) + (a3 ∗ b3)
The values inside vectors can be positive or negative integers.
You are given three input values:
* ‘vecA‘ represents the address of the first vector in memory
* ‘vecB‘ represents the address of the second vector in memory
* ‘len‘ represents the length of each individual vector
4 Part 2 - Calendar Implementation
4.1 Overview
Before the function explanation, please notice that there is a global calendar array (found at the top of part2-calendar.c). This array will hold everything related to the calendar! You will be initializing it, adding events to it, removing events from it, and much more.
The following structs will be important (found in part2-calendar.h).
typedef struct _time_ { int hour; int minute; } time;
typedef struct _event_ { char description[SIZE_DESCRIPTION]; time start; time end; } event;
typedef struct _date_ { int month; int day; int year; int num_events; event events[MAX_NUM_EVENTS];
Many of these functions return an integer flag which indicates success or failure. We have provided the macros #define ERROR -1 and #define SUCCESS 0 to help you (found in part2-calendar.h)
#define MAX_NUM_EVENTS 10 // MAX number of events
#define SIZE_DESCRIPTION 100 // MAX size of event description array
#define ERROR -1 // Code used to signal ERROR occurred
#define SUCCESS 0 // Code used to signal SUCCESS occurred
4.2 Calendar Conditions
Lastly, there are a few rules that the calendar follows.
2. ’Military Time’: Event times will be strictly in a 24 hour time scale. That is, the time division is now out of 24 hours instead of two 12 hour periods (am/pm). So, times before 1 pm are written the same way (9:01, 10:46, 12:39) but now 1:00 pm is written as 13:00 , 2:03 pm is 14:03, 3:24 pm is 15:24, 11:59 pm is 23:59 and finally 12 am is 00:00.
3. ’Event Overlap’: Calendar event times can NOT overlap in any way. For example, if an Event A starts at 2:46 and ends at 13:05 and Event B starts at 12:03 and ends at 15:32; these events are considered to be overlapping since the start of Event B is within the time range of Event A. Edge Case: if an Event A ends at 4:45 and an Event B starts at 4:45 we consider this an overlap and this should not occur.
4. An events start time can NOT be after its end time. For example, an event with a start time of 17:23 and an end time of 16:44 is considered invalid and is not allowed to be added to your calendar. Edge Case: an event starting at 14:55 and ending at 14:55 is allowed.
5. Multi-day events are not possible.
[e1,e2,e3,e4,e5]
we only consider event1 and event2 as valid events. The remaining events are garbage data and can be overwritten. If num events = 0 and the event array looks like:
[e1,e2,e3,e4,e5]
we consider e1, e2, e3, e4, and e5 to all be invalid and can be overwritten.
4.3 Functions
4.3.1 Initialize Calendar
void initialize calendar(void);
NOTE: Check section 3.2 ”Calendar Conditions” to determine edge cases.
4.3.2 Check Event Overlap
int check event overlap(event e1, event e2);
Check if events e1 and e2 have overlapping times. See Calendar Conditions ’Event Overlap’ for the definition of overlap.
If the events overlap in anyway, return ERROR. Otherwise, return SUCCESS.
NOTE: Check section 3.2 ”Calendar Conditions” to determine edge cases.
4.3.3 Add Event
If you are successful in adding the new event to the calendar return SUCCESS, otherwise return ERROR.
NOTE: Check section 3.2 ”Calendar Conditions” to determine edge cases.
4.3.4 Remove Event
If the event is removed successfully return SUCCESS, otherwise return ERROR.
Removing an event successfully requires that every subsequent event is shifted ’up’ in the array. For example, given the following event array of size 4:
[e1,e2,e3,e4]
If e2 is removed from this array the final array of size 3 will look like this:
[e1,e3,e4]
NOTE: Check section 3.2 ”Calendar Conditions” to determine edge cases.
4.3.5 Change Event Time
NOTE: Check section 3.2 ”Calendar Conditions” to determine edge cases.
4.3.6 Change Event Description
char str1[SIZE]; char str2[SIZE]; str1 = str2; // This is invalid!
When copying the new string into the description, make sure not go out of bounds of the array. If supplied a string too long to fit, truncate the string to the longest possible length that can still fit entirely in the description array.
NOTE: Check section 3.2 ”Calendar Conditions” to determine edge cases.
4.3.7 Sort Events
Unsorted: [7:42-9:12, 4:35-6:55, 3:05-4:00]
Sorted: [3:05-4:00, 4:35-6:55, 7:42-9:12] // Earliest Start Time First
Remember, this is CS 2110, we really don’t care that much about efficiency at the moment. Feel free to sort the event array with any algorithm you’d like.
NOTE: Check section 3.2 ”Calendar Conditions” to determine edge cases.
4.3.8 Destroy Calendar
void destroy calendar(void);
NOTE: Check section 3.2 ”Calendar Conditions” to determine edge cases.
5 Building & Testing
All of the commands below should be executed in your Docker container terminal, in the same directory as your project files.
5.1 Helpful Info
1. Use Docker’s ”Interactive Terminal” Run the following command in your terminal to access Docker’s terminal much easier: ./cs2110docker.sh -it
2. From within the ”Interactive Terminal” you should notice the ”host/” directory when you type ls. Navigate to your Project diretory and run the unit tests using the commands mentioned later.
3. To exit Docker’s ”Interactive Terminal” simply type: exit.
4. make is a program to help you build your project (in other words, it helps you compile).
5.2 Unit Tests
These are the same tests that will run on Gradescope To run the autograder locally (without GDB):
1. make clean - Clean your working directory
2. make tests - Compile all the required files
3. ./tests - Run the unit tests
4. make - Compile all the required files and Run the unit tests (previous two steps with one command)
Executing ./tests will run all the test cases and print out a percentage, along with details of the failed test cases.
Other available commands (after running make tests):
• To run a specific test case (to avoid all printing output/debug messages for all test cases):
make run-case TEST=testCaseName Example: make run-case TESTS=test_compare
• To run a test case with gdb:
make run-gdb TEST=testCaseName (or no testCase to run all in gdb)
5.3 Write Your Own Tests
In your Project 4 directory there is a file named ”main.c”. This file can be used to make your own tests. The main method provided can be executed with the following command.
1. make student
For example, if you want to write a test for your ”compare” function from Part 1 you can do the following in the main.c file:
int main(void) {
int a = 2; int b = 3;
int test_value = compare(a, b); printf("Expected Return Value: -1 Actual Return Value: %d ", test_value);
return 0;
}
Then execute make student inside Docker. Then, assuming your function is correct, you should receive an output similar to this:
Expected Return Value: -1
Actual Return Value: -1
6 Deliverables
Please do not wait until the last minute to run/test your project, history has proved that last minute turn-ins will result in long queue times for grading on Gradescope. You have been warned!!!
NOTE: The syllabus states the following requirement is met - ”Your code must compile with gcc on Ubuntu 18.04 LTS. If your code does not compile, you will receive a 0 for the assignment.” HOWEVER, for this project your code MUST compile on our Docker image otherwise you will receive a 0.
7 Demos
• Sign up for a demo time slot via Canvas before the beginning of the first demo slot. This is the only way you can ensure you will have a slot.
• Your overall project score will be ((autograder_score * 0.5) + (demo_score * 0.5)), meaning if you received a 90% on your autograder, but a 30% on the demo you would receive an overall score of 60%. If you miss your demo you will not receive any of these points and the maximum you can receive on the project is 50%.
• You will be able to makeup one of your demos at the end of the semester for half credit.
8 Rules and Regulations
8.1 General Rules
2. Please read the assignment in its entirety before asking questions.
4. If you find any problems with the assignment, it would be greatly appreciated if you reported them to the author (which can be found at the top of the assignment). Announcements will be posted if the assignment changes.
8.2 Submission Conventions
2. Do not submit links to files. The autograder does not understand it, and we will not manually grade assignments submitted this way as it is easy to change the files after the submission period ends.
8.3 Submission Guidelines
2. You are also responsible for ensuring that what you turned in is what you meant to turn in. After submitting you should be sure to download your submission into a brand new folder and test if it works. No excuses if you submit the wrong files, what you turn in is what we grade. In addition, your assignment must be turned in via Canvas/Gradescope. Under no circumstances whatsoever we will accept any email submission of an assignment. Note: if you were granted an extension you will still turn in the assignment over Canvas/Gradescope.
4. Projects turned in late receive partial credit within the first 48 hours. We will take off 30% of the points for a project submitted between 0 and 24 hours late, and we will take off 50% of the points for a project submitted between 24 and 48 hours late. We will not accept projects turned in over 48 hours late. This late policy is also in the syllabus. The late policy is applied to both portions of the project; turning the code in late means that you will also lose points on the demo.
8.4 Syllabus Excerpt on Academic Misconduct
Academic misconduct is taken very seriously in this class.
3. A student must submit an assignment or project as his/her own work (this is what is expected of the students).
8.5 Is collaboration allowed?