Design and Implement a double linked list in C++ with the following operations:

a- Create "n" nodes b- Delete from the end c- Insert at the beginnin

I have it almost complete. I just need to fix the function void insertdata(int x) since it does not insert data at the begining of the node as it is suppoused to do. Could somebody fix that function for me? This is the code I have so far:

#include

#include

using namespace std;

//Define node structure

struct node

{

int data;

node *prev;

node *next;

};

node *top = NULL;

//Creates a node

node *getnode()

{

node *newnode;

newnode = (node*)malloc(1000);

cout << " Enter Data: ";

cin >> newnode->data;

newnode->next = NULL;

return newnode;

}

//Insert date at the beginning

void insertdata(int x)

{

node *newnode, *temp, *prev;

int pos, nodectr;

int ctr = 1;

cout << " Enter the data to insert: ";

newnode = getnode();

if (top == NULL)

{

top = new node;

top->data = x;

top->next = NULL;

top->prev = NULL;

}

else

{

node *n = new node;

n->data = x;

n->next = top;

n->prev = NULL;

top->prev = n;

top = n;

}

}

//Display the list

void displayList()

{

cout << "Elements : ";

node *disp = top;

while (disp != NULL)

{

cout << " " << disp->data;

if (disp->next == NULL)

{

break;

}

disp = disp->next;

}

}

//Delete last node

void deleteLast()

{

node *del = top;

node *prev;

while (del->next != NULL)

{

prev = del;

del = del->next;

}

prev->next = NULL;

}

//Creates a list with size N

void creatlist(int n)

{

int i;

node *newnode;

node * temp;

for (i = 0; i < n; i++)

{

newnode = getnode();

if (top == NULL)

{

top = newnode;

}

else

{

temp = top;

while (temp->next != NULL)

{

temp = temp->next;

}

temp->next = newnode;

}

}

}

int main()

{

node n;

char ch;

int no;

do

{

cout << endl << "a - Create \"n\" nodes.";

cout << endl << "b - Delete from the end.";

cout << endl << "c - Insert at the begining.";

cout << endl << "d - Display.";

cout << endl << "q - Quit.";

cout << endl << "Please enter your choice: ";

cin >> ch;

switch (ch)

{

case 'A': case 'a':

cout << " Enter the size of Linked List: ";

cin >> no;

creatlist(no);

break;

case 'B': case 'b':

{

deleteLast();

cout << "Last element was deleted";

}

break;

case 'C': case 'c':

insertdata(no);

break;

case 'D': case 'd':

displayList();

break;

case 'Q': case 'q':

exit(0);

default:

cout << " Invalid choice, try again";

}

} while (1);

}