Middle Node

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Unit 5 Session 1 (Click for link to problem statements)

U-nderstand

Understand what the interviewer is asking for by using test cases and questions about the problem.

• How does the insertion of a new node affect the existing structure of the linked list?
  • The new node (middle) is placed between two existing nodes (head and tail), changing the next references to maintain the list order.

P-lan

Plan the solution with appropriate visualizations and pseudocode.

General Idea: Insert the middle node between head and tail by adjusting the next pointers to link all three nodes sequentially.

1) Create the `middle` node with a value of 150, initially linking it directly to `tail`.
2) Adjust the `next` pointer of the `head` node to point to the new `middle` node.
3) This establishes the order: head -> middle -> tail in the linked list.

⚠️ Common Mistakes

• Incorrectly setting the next pointers could disrupt the linked list's structure, either by skipping a node or creating a loop.
• Not understanding the initial conditions from previous problems could lead to incorrect linking.

I-mplement

# Existing code
head = Node(100)
tail = Node(200)
head.next = tail

middle = Node(150, tail)
head.next = middle