Question

Suppose head is a head reference for a linked list of integers. Write a few lines of code that will add a new node with the number 42 as the second element of the list. (If the list was originally empty, then 42 should be added as the first node instead of the second.)

Answer 1

To add a new node with the number 42 as the second element of the linked list, create a new node and update the references accordingly.

Step-by-step explanation:

To add a new node with the number 42 as the second element of the linked list, we need to create a new node and update the references accordingly.

If the list is empty, we can simply create a new node and make 'head' point to it. Otherwise, we need to traverse the list and find the first node. Then, we create a new node and update its next reference to point to the node that head is currently pointing to. Finally, we update the next reference of the first node to point to the newly created node.

Node newNode = new Node(42);

if (head == null) {
head = newNode;
} else {
Node firstNode = head;
newNode.next = firstNode.next;
firstNode.next = newNode;
}