Most of the main is already done. You only need to focus on the 6 functions, and that's it.
COP3502C Computer Science 1 Dr. Andrew Steinberg Spring 2022 Programming Assignment 1 Tell me a Random Story Max Points 100 Due: 2/6/2022 at 11:59pm Background Story of this Assignment All of you should of passed COP3223C Introduction to Programming in C (or a similar course) to be enrolled in CS1. Some of you took the prerequisite last semester, some of you may have taken the prerequisite two semesters ago, and some of you may have taken the prerequisite over a year ago or more. Nevertheless, the goal of this assignment is to serve as a warmup with dynamic memory as it will play a heavy role in learning our data structures for CS1. If it has been months since you worked with C, then you may feel a little rusty (don’t worry that is normal). That is why the first assignment is a review from some prerequisite topics (such as strings and dynamic memory). However, it is critical, to regain these skills in dynamic memory, strings, and structs (even though this assignment doesn’t cover structs) so we can smoothly cover data structures and learn their ADT. In this assignment, we will touch upon the topics of strings and dynamic memory. You are going to create a program that generates random sentences. These random sentences won’t make sense however we will still follow the general rules of English of forming one. Since we are going to generate random sentences, we will also create the most random story that won’t even make sense. Start Early and see the TAs and ULAs! They are here to help you! Don’t procrastinate! Assignment Details This section covers the assignment in more detail. • The random sentence generated will be formulated by these types of words. sentence = article1 adjective1 noun1 verb preposition article2 adjective2 noun2 Note: The subscript represents that a different word of the respective category can be generated. For example article1 = ”The” and article2 = ”A”. • Here is a sample random sentence generated from the working program using the sentence formula from above. Sometimes words picked from respective categories can be the same (such as the article and adjective in this case). Note that there is one blank white space between each word and a period at the end of the sentence. Here is another example where each word from the categories are all unique. COP3502C Computer Science 1 Dr. Andrew Steinberg Spring 2022 • You might notice that the first letter in articles are all capitalized. This is due that the sentence formula starts with an article. Make sure for the articles, that they are all capitalized with the first letter. It should already be provided that way for you in the C file on Webcourses. Do not change it! • You will use 5 separate dynamic 2D arrays (utilizing double pointers) in storing the respective words in their respective categories (noun, verb, adjective, preposition, and article). The Provided Skeleton File You were provided with a skeleton C file that has the main function and function prototypes. This section will discuss the lines of code provided for you in the main function to assist you with understanding how the code will execute. • Lines 6 – 9 are preprocessor directive statements. The first three import content from the standard I/O library, standard library, and string library. This will allow you to use certain built in functions in completing the assignment. • Line 9 defines a macro constant called LIMIT that holds the value 20. This will be number of characters a string can store. That means the words being read can only be of size 19 (we have to include \0 character). • Lines 11 – 16 are the function prototypes. This is discussed in the next section in more detail. • Lines 18 – 126 is the main function. Let’s divide up parts of the main function. o Lines 21 – 24 sets up the randomness of our program. This will low the script the grader use in determining a random scenario to truly check your work properly. o Line 24 calls srand(). This is a function part of stdlib that generates a seed for the pseudo random generator. This will allow you to run the code with the same scenario repeatedly. If you change the seed, then you will get a different scenario which will result in a different output. o Lines 27 – 30 declares/initializes variables that keeps track of the size each dynamic 2D arrays of each category respectively currently stores. In simple terms, it will tell you how many words are in each category. They start empty which is why is 0 is the first value assigned. o Line 32 – 36 declares/initializes variables that keeps track of the max size each dynamic array can hold. In simple terms, it keeps track of how much the heaps can store fully (number of elements). Note: The number of articles used is 3 (“a”, “an”, and “the”). That is why const is used since we will not be changing the size of the array during the program run. o Lines 41 – 45 declares 5 double char pointers and assigns them to NULL. o Lines 47 – 51 assigns each of the double char pointers to a heap of single char pointers. o Lines 54 – 59 checks to make sure that the previous malloc call was successful in providing an address to a heap. If it was not successful then, the program terminates. o Lines 62 – 67 populates the articles 2D array with the respective three articles used in the English Language. It also allocates a heap to store the string. COP3502C Computer Science 1 Dr. Andrew Steinberg Spring 2022 o Lines 70 – 73 opens the text files of words of each respective category. Those text files must be in the same directory as your C file. o Lines 76 – 81 checks to make sure the files were properly opened, otherwise the program terminates. o Lines 84 – 87 calls a user defined function (you will have to implement) populate that will fill the dynamic arrays with the respective words in their category. Details of populate are in the section. o Lines 90 – 93 closes the text files since they will no longer be needed. The words should be in the 2D dynamic arrays. o Lines 99 – 104 contains a for loop that will generate some random sentences. This is done by the user defined function generatesentence (which you will implement). Line 101 specifically calls a user defined function displaysentence that will display a random sentence to the terminal window. Line 103 frees the heap to prevent memory leaks. Think about how this will relate to the function generatesentence. That is part of the challenge. o Lines 106 – 117 will open 3 text files to store 3 random stories respectively. o Line 119 calls a user defined function cleanUp that frees any heap memory in use. You will have to implement this user defined function. That is part of the challenge. The Function Prototypes You are going to implement 6 user defined functions. In the provided main function, you were provided the prototypes. This section will describe what it is expected from each definition. void displaysentence(char * sentence); The displaysentence function will display the sentence to the terminal window. The function takes one argument which is a char pointer (dynamic string) and will display it on a single line. Here is a sample screenshot of the function being called three times consecutively. char ** populate(char ** words, FILE *fptr, int *currentsize, int *maxsize); The populate function will assign actual values to the dynamic array. It will fill it with strings from the provided text files. The function will return the populated 2D dynamic string array. The functions takes 4 arguments: 1. A double pointer of type char called words. This is a 2D dynamic array that contains words (strings) from the respective category (noun, verb, adjective, preposition). 2. A file pointer that contains the location of the text file from being read. The file should be open in the main function. 3. A pointer of type int called currentsize. This pointer holds the address of an integer that keeps track of the amount of strings stored in the 2D dynamic array. COP3502C Computer Science 1 Dr. Andrew Steinberg Spring 2022 4. A pointer of type int called maxsize. This pointer holds the address of an integer that keeps track of the maximum amount of strings the 2D dynamic array can store. There are some things you need to consider for this function implementation. • When allocating heap space for the string, make sure it was successful. Remember malloc doesn’t always return an address. Perform the necessary action recommended if that is the case. It is good practice to prevent segmentation faults. • When the program starts running, the 2D dynamic array starts with 5 strings it can hold potentially. However, you will notice that the provided text files has more than 5 strings to read. That means we will need to allocate more heap space some how. Think about how doubleIt will work in this scenario. That is part of the challenge in this assignment. char ** doubleIt(char **arr, int *maxsize); The doubleIt function will increase the heap size by doubling the original space. The functions takes 2 arguments: 1. A double pointer of type char called arr. This is a 2D dynamic array that contains words (strings) from the respective category (noun, verb, adjective, preposition). This is the original heap. 2. A pointer of type int called maxsize. This pointer holds the address of an integer that keeps track of the maximum amount of strings the 2D dynamic array can store. When this function is invoked, the current size of the dynamic array is at capacity so the values should match. This value will need to be multiplied by 2. The function allocates a new heap that is twice the size of the original heap and copy the values from the original heap into the new heap. One important note about this is that you have to properly copy the values over in order to avoid segmentation fault. Think about how this can be avoided.