Question Discussion & Solution

struct node {
      int data;
      struct node *next;
}start = NULL;
struct node *new_node;

a)

public void insertHead(int data)
{
 Node temp = new Node(data);
 Node cur = head;
 while(cur.getNext() != head)
  cur = cur.getNext()
 if(head == null)
 {
  head = temp;
  head.setNext(head);
 }
 else
 {
  temp.setNext(head);
  head = temp;
  cur.setNext(temp);
 }
 size++;
}

b)

public void insertHead(int data)
{
 Node temp = new Node(data);
 while(cur != head)
  cur = cur.getNext()
 if(head == null)
 {
  head = temp;
  head.setNext(head);
 }
 else
 {
  temp.setNext(head.getNext());
  cur.setNext(temp);
 }
 size++;
}

c)

public void insertHead(int data)
{
 Node temp = new Node(data);
 if(head == null)
 {
  head = temp;
  head.setNext(head);
 }
 else
 {
  temp.setNext(head.getNext());
  head = temp;
 }
 size++;
}

d)

public void insertHead(int data)
{
 Node temp = new Node(data);
 if(head == null)
 {
  head = temp;
  head.setNext(head.getNext());
 }
 else
 {
  temp.setNext(head.getNext());
  head = temp;
 }
 size++;
}