Solve :- insert a node at the start of a DLL
// Function to insert a node at the beginning of the doubly linked list
struct Node* insertAtBeginning(struct Node* head, int value)
{
// Step 1: Create a new node with the given value
struct Node* newNode = createNode(value);
// Step 2: If the list is not empty, update the current head's previous pointer
if (head != NULL)
{
head->prev = newNode;
}
// Step 3: Make the new node's next pointer point to the current head
newNode->next = head;
// Step 4: Update the head to point to the new node
head = newNode;
// Return the new head of the list
return head;
}
Write a function to sort a DLL
sort(struct node **head)
// pointer to the pointer of the head node of the linked list.
{
struct node *n, *c;
// declares two pointers to nodes in a linked list.
int x;
for (c = *head; c-> next ! = NULL, c = c->next)
// c = *head: Start at the first node of the list.
// c->next != NULL: Check if the current node has a next node; continue if true.
// c = c->next: Move to the next node in the list.
for(n = c->next; n!=NULL; n=n->next)
{
//compare (swap logic)
If(c->data > n->data)
{
X = c->data;
c->data = n->data;
n->data = x;
}
}
}
Reverse print a DLL without using recursion
d_rdisplay( struct dnode *q )
{
Struct dnode *temp=*q;
while ( temp->next != NULL )
//checks if the current node (temp) has a next node (i.e., temp->next is not NULL).
temp = temp->next;
//temp = temp->next;: This moves the pointer temp to the next node in the list.
while(temp!=NULL)
{
printf ( "%d ", temp -> data ) ;
temp = temp -> next ;
}
}
The code loops through the linked list, printing the data of each node, and moves to the next node until it reaches the end (when temp is NULL).
