Lab6.c

/********* Lab6 *******
*   Course: PROG1955-1
*    Title: Lab6
*  Purpose: Store the last name and first name of students in a dynamic 
            structure using a linked list
*     Date: 2018-11-10
*   Author: 
*     File: Lab6.c
*/

#include <stdio.h>
#include <stdlib.h>

struct studentRecord
{
	char *firstName;
	char *lastName;

	struct studentRecord *nextPtr;
};

typedef struct studentRecord StudentRecord;

StudentRecord * createRecord(char *firstName, char *lastName);
void printRecord(StudentRecord *r);
int insertRecord(StudentRecord **headPtr, StudentRecord *r);
void listRecords(StudentRecord **headPtr);

StudentRecord * createRecord(char *firstName, char *lastName)
{
	StudentRecord *r = malloc(sizeof(StudentRecord));
	r->firstName = firstName;
	r->lastName = lastName;
	r->nextPtr = NULL;
	return r;
}

void printRecord(StudentRecord *r)
{
	printf("First name: %s, Last name: %s\n", r->firstName, r->lastName);
}

int insertRecord(StudentRecord **headPtr, StudentRecord *r)
{

	StudentRecord *previousPtr = NULL;
	StudentRecord *currentPtr = *headPtr;

	// Find the last item in the list
	while (currentPtr != NULL)
	{
		previousPtr = currentPtr;
		currentPtr = currentPtr->nextPtr;
	}

	if (previousPtr == NULL)
		// This is the first record to be added to the list
	{
		r->nextPtr = *headPtr;
		*headPtr = r;
		puts("first!");
	}
	else
	{
		// Append the new item to the end of the list, with the
		// last item becoming the second-last item.
		previousPtr->nextPtr = r;
		r->nextPtr = currentPtr;
	}
	return 1;

}

void listRecords(StudentRecord **headPtr)
{
	StudentRecord *currentPtr = NULL;

	currentPtr = *headPtr;

	if (currentPtr == NULL)
		// No records in this list
	{
		puts("Empty.");
		return;
	}

	do
	{
		printRecord(currentPtr);
		currentPtr = currentPtr->nextPtr;

	} while (currentPtr != NULL);
	
	puts("End of list.");
	
	return;
}

int main()
{
	char first1[] = "Chris";
	char last1[] = "Niceguy";
	char first2[] = "Jason";
	char last2[] = "Otherguy";

	char *f1 = first1;
	char *l1 = last1;

	char *f2 = first2;
	char *l2 = last2;

	// This is the pointer to the first record in our list
	StudentRecord *headPtr = NULL;

	// This are record pointers for testing, all records will be created in the loop
	StudentRecord *newRecord1 = NULL;
	StudentRecord *newRecord2 = NULL;

	newRecord1 = createRecord(f1, l1);
	insertRecord(&headPtr, newRecord1);
	newRecord2 = createRecord(f2, l2);
	insertRecord(&headPtr, newRecord2);

	listRecords(&headPtr);

	return 0;
}