// CSE240 Fall 2022 HW6

// Write your name here

// Write the compiler used: Visual studio or gcc

#include

#include

#include

#pragma warning(disable: 4996) // for Visual Studio Only

#define MAX_INSTRUCTORS 20

#define MAX_NAME_LENGTH 50

typedef enum { cs = 0, physics, mathematics, english }departmentEnum; // enum type

struct instructorRecord { // struct for instructor details

char name[MAX_NAME_LENGTH];

departmentEnum department;

unsigned int instructorId;

unsigned int age;

struct instructorRecord* next; // pointer to next node

}*list = NULL; // declare linked list 'list'

int count = 0; // the number of instructors currently stored inthe list (initialized to 0)

// functions already implmented

void flushStdIn();

void executeAction(char);

void save(char* fileName);

// functions that need implementation:

int add(char* name_input, unsigned int instructorId_input,unsigned int age_input, char* department_input); // 10 points

void sort(); // 10 points

int delete(unsigned int instructorId_input); // 10 points

void load(char* fileName); // 10 points

void display(); // 10 points

int main()

{

char* fileName = "Instructor_List.txt";

load(fileName); // load list of instructors from file (if itexists). Initially there will be no file.

char choice = 'i'; // initialized to a dummy value

do

{

printf("Enter your selection:");

printf("t a: add a new instructor");

printf("t d: display instructor list");

printf("t r: remove an instructor from list");

printf("t s: sort instructor list by ID");

printf("t q: quit");

choice = getchar();

flushStdIn();

executeAction(choice);

} while (choice != 'q');

save(fileName); // save list of instructors to file (overwritesfile, if it exists)

return 0;

}

// flush out leftover '' characters

void flushStdIn()

{

char c;

do c = getchar();

while (c != '' && c != EOF);

}

// ask for details from user for the given selection and performthat action

void executeAction(char c)

{

char name_input[MAX_NAME_LENGTH];

unsigned int instructorId_input, age_input, add_result = 0;

char department_input[20];

switch (c)

{

case 'a':

// input instructor record from user

printf("Enter instructor name: ");

fgets(name_input, sizeof(name_input), stdin);

name_input[strlen(name_input) - 1] = '0'; // discard thetrailing '' char

printf("Enter instructor department(cs/physics/mathematics/english): ");

fgets(department_input, sizeof(department_input), stdin);

department_input[strlen(department_input) - 1] = '0'; //discard the trailing '' char

printf("Please enter instructor ID number: ");

scanf("%d", &instructorId_input);

printf("Please enter instructor age: ");

scanf("%d", &age_input);

flushStdIn();

// add the instructor to the list

add_result = add(name_input, instructorId_input, age_input,department_input);

if (add_result == 0)

printf("Instructor is already on the list! ");

else if (add_result == 1)

printf("Instructor successfully added to the list! ");

else

printf("Unable to add. Instructor list is full! ");

break;

case 'r':

printf("Please enter instructor ID to be deleted: ");

scanf("%d", &instructorId_input);

flushStdIn();

int delete_result = delete(instructorId_input);

if (delete_result == 0)

printf("Instructor not found in the list! ");

else

printf("Instructor deleted successfully! ");

break;

case 'd': display(); break;

case 's': sort(); break;

case 'q': break;

default: printf("%c is invalid input!", c);

}

}

// Q1 : add (10 points)

// This function is used to add an instructor into the list. Youcan simply add the new instructor to the end of list (linked listof structs).

// Do not allow the instructor to be added to the list if italready exists in the list. You can do that by checking instructornames OR IDs already in the list. If either condition matches,return 0 without adding it to the list.

// If the instructor already exists then return 0 without addingit to the list. If the instructor does not exist in the list thenadd the instructor at the end of the list and return 1.

// If instructor list is full, then do not add new instructor tothe list and return 2.

// NOTE: Notice how return type of add() is checked in case 'a'of executeAction()

// NOTE: You must convert the string 'department_input' to anenum type and store it in the list because the department has enumtype (not string type). Any incorrect or mistyped values will bedefaulted to "english".

// The list should be case sensitive. For instance, 'Roger' and'roger' should be considered two different names.

// Hint: 'count' holds the number of instructors currently inthe list

int add(char* name_input, unsigned int instructorId_input,unsigned int age_input, char* department_input)

{

struct instructorRecord* tempList = list; // work on a copy of'list'.

// Write the code below

return 0; // edit this line as needed

}

// This function displays the instructor list with the details(struct elements) of each instructor.

// Q2. display (10 points)

// Display all instructors.

void display()

{

struct instructorRecord* tempList = list; // work on a copy of'list'

// Write the code below

}

// Q3 : sort (10 points)

// This function is used to sort the list(linked list ofstructs) numerically in ascending order by instructor ID.

// Parse the list and compare the instructor IDs to check whichone should appear before the other in the list.

// Sorting should happen within the list. That is, you shouldnot create a new node of structs having sorted books.

void sort()

{

struct instructorRecord* tempList = list; // work on a copy of'list'

// Write the code below

// display message for user to check the result of sorting.

printf("Instructor list sorted! Use display option 'd' to viewsorted list.");

}

// save() is called at the end of main()

// This function saves the linked list of structures tofile.

// save() is called at end of main() to save the instructor listto a file.

// The file is saved at the same place as your C file. For VS,the default directory looks like this:

// C:UsersDocumentsVisual Studio2017ProjectsProject1Project1

// You can simply delete the file to 'reset the list' or toavoid loading from it.

void save(char* fileName)

{

struct instructorRecord* tempList = list; // work on a copy of'list'

FILE* file;

int departmentValue = 0;

file = fopen(fileName, "wb"); // open file for writing

fwrite(&count, sizeof(count), 1, file); // First, store thenumber of books in the list

// Parse the list and write instructor record to file

while (tempList != NULL) {

fwrite(tempList->name, sizeof(tempList->name), 1,file);

// convert enum to a number for storing

// cs = 0, physics = 1, mathematics = 2, english = 3

if (tempList->department == cs)

departmentValue = 0;

else if (tempList->department == physics)

departmentValue = 1;

else if (tempList->department == mathematics)

departmentValue = 2;

else

departmentValue = 3;

fwrite(&departmentValue, sizeof(departmentValue), 1,file);

fwrite(&tempList->instructorId,sizeof(tempList->instructorId), 1, file);

fwrite(&tempList->age, sizeof(tempList->age), 1,file);

tempList = tempList->next;

}

fclose(file); // close the file after writing

}

// Q4 : delete (10 points)

// This function is used to delete an instructor by ID.

// Parse the list and compare the instructor IDs to check whichone should be deleted.

// Return 0 if the specified ID was not found. Return 1 uponsuccessful removal of a record.

int delete(unsigned int instructorId_input)

{

struct instructorRecord* tempListCur = list; // work on a copyof 'list'

struct instructorRecord* tempListPrev = list; // work on a copyof 'list'

// Write the code below

return 0; // edit this line as needed

}

// Q5: load (10 points)

// This function is called in the beginning of main().

// This function reads the instructor list from the saved fileand builds the linked list of structures 'list'.

// In the first run of the program, there will be no saved filebecause save() is called at the end of program.

// So at the begining of this function, write code to open thefile and check if it exists. If file does not exist, then returnfrom the function.

// (See expected output of add() in homework question file. Itdisplays "Instructor_List.txt not found" because the file did notexist initially.)

// If the file exists, then parse the instructor list to readthe instructor details from the file.

// Use the save function given above as an example of how towrite this function. Notice the order in which the struct elementsare saved in save()

// You need to use the same order to read the list back.

// NOTE: The saved file is not exactly readable because allelements of the struct are not string or char type.

// So you need to implement load() similar to how save() isimplemented. Only then the 'list' will be loaded correctly.

// You can simply delete the file to 'reset the list' or toavoid loading from it.

void load(char* fileName)

{

struct instructorRecord* tempList = list; // work on a copy of'list'

// Write the code below

}