QUESTION 1.

Consider the following linked list node structure:

struct node{

int data;

struct node *next;

};

Implement the following basic functions of the linear linked list structure:

1. Check empty list

int is_empty( struct node *header)

{

if(header==NULL)

return 1; //TRUE

else

return 0; //FALSE

}

2. Create a node

struct node * newnode(int d)

{

struct node *temp;

temp=(struct node *) malloc(sizeof(node));

temp->data =d;

temp->next=NULL;

return temp;

}

3. Insert a node into front/back/middle of LL

struct node * insertFront(struct node *header, int d)

{

struct node *temp;

temp=newnode(d);

temp->next =header;

header=temp;

return header;

}

struct node * insertBack(struct node *header, int d)

{

struct node *temp, *headertemp;

temp=newnode(d);

if(header==NULL)

{

header=temp;

return header;

}

headertemp=header;

while(headertemp->next!=NULL)

headertemp =headertemp->next;

headertemp->next=temp;

return header;

}

void insertAfter(struct node *afterNode, int d)

{

struct node *temp;

temp=newnode(d);

temp->next=afterNode->next;

afterNode->next=temp;

}

4. Delete a node from front/back/middle of LL

struct node * deleteFront(struct node *header)

{

struct node *temp;

if(header==NULL)

return header;

temp=header;

header= header->next;

free(temp);

return header;

}

struct node * deleteBack(struct node *header)

{

struct node *temp, *headertemp;

if(header==NULL)

return header;

headertemp=header;

while(headertemp->next->next!=NULL)

headertemp =headertemp->next;

temp=headertemp->next;

headertemp->next=NULL;

free(temp);

return header;

}

void deleteAfter(struct node *afterNode)

{

struct node *temp;

if(afterNode->next==NULL || afterNode==NULL)

return;

temp =afterNode->next;

afterNode->next=temp->next;

free(temp);

}

Task 1: Write down a complete C/C++ program to test your linear linked list implementation. Additionally, write another function which will be used to list the linked list content. Complete your implementation using the following code:

header = insertBack(header,2);

header = insertBack(header,4);

header = insertBack(header,6);

DisplayList(header);

header = insertFront(header,1);

DisplayList(header);

insertAfter(header->next->next,5);

DisplayList(header);

header = deleteFront(header);

DisplayList(header);

header = deleteBack(header);

DisplayList(header);

deleteAfter(header->next);

DisplayList(header);

Task 2: Write a function that finds the average of the elements of a linked list. Use the following prototype. Modify your linked list data field to be a float and insert initial floats (1.5, 2.5, 3.5, 4.5) to test your function.

float averagelist (struct node *);

Task 3: Write a function that counts and returns 'A' grades which are stored in the linked list. Use the following prototype. Modify your linked list data field to be a character and insert initial characters (A,B,A,C,D) to test your function.

int countA (struct node *);