Question

IN C Programming

#include<stdio.h>

#include<stdlib.h>

typedef struct nodestruct {

int item;

struct nodestruct *next;

} Node;

typedef struct {

int size; // Number of items on user’s list

Node *head, *tail;

} List;

//In addition to creating an empty list, this function will also create two dummy nodes; one for the head, and the other for the tail.
List* createList();

//This function creates a node containing the provided item, then inserts it into the list pointed by the provided list pointer at a location provided by the index. Finally, it should return an updated list pointer. Note: index is zero based, starting from the first node following the dummy node. The function should be able to print out an error message if the index is beyond the size of the list and returns the un-updated list pointer.
List* insertNode(List* , int, int);

//This function removes the node at the location provided by the index from the provided list pointer. Note: index is zero based, starting from the first node following the dummy node. The function should be able to print out an error message if the index is beyond the size of the list.
void removeNode(List*, int);

Hint: Modify the printList function since we use dummy nodes here.

Main description:
1. Using the provided two ADTs, create a list with two dummy nodes.
2. Generate an array with 5 random integer numbers between 1 and 10. Print out the 'generated' numbers on the console separated by space.
3. Insert each of the generated numbers in the list using the example FOR LOOP as below.
for (int i = 0; i<5; i++){
list = insertNode(list, i, array[i]);
}
4. Print the contents of the list on the console separated by space.
5. Now, insert 15 at the 0th index of the list. Next, insert 20 at the 3rd index of the list. Finally insert 25 at the 10th index of the list.
6. Print the contents of the list on the console separated by space.
7. Remove the node at the 4th index of the list. Next, remove the node at the 1st index of the list. Finally remove the 11th index of the list.
8. Print the contents of the list on the console separated by space.



Example output:

mwc-070138:~ $ gcc main.c lab8.c -Wall -Werror
mwc-070138:~ $ ./a.out
Randomly 'generated' numbers: 1 3 7 2 10

Items on the list: 1 3 7 2 10

Index 10 does not exist. Unable to insert!

Items on the list: 15 1 3 20 7 2 10

Removed item is 7
Removed item is 1
Index 11 does not exist. Unable to remove!

Items on the list: 15 3 20 2 10

Answer 1

Here is the code for you:

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

typedef struct nodestruct {
int item;
struct nodestruct *next;
} Node;

typedef struct {
int size; // Number of items on user’s list
Node *head, *tail;
} List;

//In addition to creating an empty list, this function will also create two dummy nodes;
//one for the head, and the other for the tail.
List* createList();

//This function creates a node containing the provided item, then inserts it into the list
//pointed by the provided list pointer at a location provided by the index. Finally, it
//should return an updated list pointer. Note: index is zero based, starting from the
//first node following the dummy node. The function should be able to print out an error
//message if the index is beyond the size of the list and returns the un-updated list pointer.
List* insertNode(List* , int, int);

//This function removes the node at the location provided by the index from the provided
//list pointer. Note: index is zero based, starting from the first node following the
//dummy node. The function should be able to print out an error message if the index is
//beyond the size of the list.
void removeNode(List*, int);

//Hint: Modify the printList function since we use dummy nodes here.
void printList(List*);

int main()
{
    //Main description:
    //1. Using the provided two ADTs, create a list with two dummy nodes.
    List *myList = createList();
   
    //2. Generate an array with 5 random integer numbers between 1 and 10.
    //Print out the 'generated' numbers on the console separated by space.
    int array[5];
    for(int i = 0; i < 5; i++)
        array[i] = rand() % 10 + 1;
    printf("Randomly 'generated' numbers: ");  
    for(int i = 0; i < 5; i++)  
        printf("%i ", array[i]);
    printf("\n");
   
    //3. Insert each of the generated numbers in the list using the example FOR LOOP as below.
    for (int i = 0; i<5; i++){
        myList = insertNode(myList, i, array[i]);
    }
   
    //4. Print the contents of the list on the console separated by space.
    printList(myList);
   
    //5. Now, insert 15 at the 0th index of the list.
    //Next, insert 20 at the 3rd index of the list.
    //Finally insert 25 at the 10th index of the list.
    myList = insertNode(myList, 0, 15);
    myList = insertNode(myList, 3, 20);
    myList = insertNode(myList, 10, 25);
   
    //6. Print the contents of the list on the console separated by space.
    printList(myList);
   
    //7. Remove the node at the 4th index of the list.
    //Next, remove the node at the 1st index of the list.
    //Finally remove the 11th index of the list.
    removeNode(myList, 4);
    removeNode(myList, 1);
    removeNode(myList, 11);
   
    //8. Print the contents of the list on the console separated by space.
    printList(myList);
}
void printList(List* myList)
{
    Node* temp = myList->head;
    printf("Items on the list: ");
    while(temp != NULL)
    {
       printf("%i ", temp->item);
       temp = temp->next;
    }  
    printf("\n");
}   
List* createList()
{
    List* myList;
    myList->head = myList->tail = NULL;
    myList->size = 0;
    return myList;
}

List* insertNode(List* myList, int pos, int value)
{
    Node* myNode = malloc(sizeof(Node));
    myNode->item = value;
    if(pos == 0)   //Element being inserted at the start of the list.
    {
       myNode->next = myList->head;
       myList->head = myNode;
       if(myList->size == 0)
           myList->tail = myNode;
       (myList->size)++;  
    }
    else if(pos == myList->size) //Element being inserted at the end of the list.
    {
       myNode->next = NULL;
       myList->tail->next = myNode;
       myList->tail = myNode;
       (myList->size)++;
    }
    else if(pos > myList->size)
        printf("Index %d does not exist. Unable to insert!\n", pos);
    else
    {
       Node* temp = myList->head;
       for(int i = 0; i < pos-1; i++)
           temp = temp->next;
       myNode->next = temp->next;
       temp->next = myNode;
       (myList->size)++;  
    }  
    return myList;
}

void removeNode(List* myList, int pos)
{
    Node* temp = myList->head;
    if(pos < 0 || pos >= myList->size)
       printf("Index %d does not exist. Unable to remove!\n", pos);
    else if(pos == 0)
    {
        myList->head = myList->head->next;
        printf("Removed item is %d\n", temp->item);
        free(temp);
        (myList->size)--;
        if(myList->size == 0)
            myList->tail = NULL;
    }  
    else
    {
        for(int i = 0; i < pos-1; i++)
            temp = temp->next;
        Node* other = temp->next;
        if(myList->tail == other)
            myList->tail = temp;
        temp->next = temp->next->next;
        printf("Removed item is %d\n", other->item);
        free(other);  
        myList->size--;
    }
}

And the output screenshot is: