Reorder List
Detailed guide and Python implementation for the 'Reorder List' problem.
Problem Statement
You are given the head of a singly linked list. The list can be represented as:
L0 → L1 → … → Ln-1 → Ln
Reorder the list to be in the following form:
L0 → Ln → L1 → Ln-1 → L2 → Ln-2 → …
You may not modify the values in the list's nodes. Only nodes themselves may be changed.
The linked list is represented as a Python list. Implement a function reorderList(head: list) -> list that returns the reordered list.
- •The number of nodes in the list is in the range [1, 50000]
- •1 <= Node.val <= 1000
Examples
[1,2,3,4]
[1,4,2,3]
The list 1->2->3->4 is reordered to 1->4->2->3.
[1,2,3,4,5]
[1,5,2,4,3]
The list 1->2->3->4->5 is reordered to 1->5->2->4->3.
Need a Hint?
Edge Cases to Watch
- Empty input structures
- Single element inputs
- Large numerical bounds
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