Challenge Statement
- Given the
headof a singly linked list, reverse the list, and return the reversed list. - This challenge corresponds to LeetCode #206.
Constraints
- The number of nodes in the list is the range
[0, 5000]. -5000 <= Node.val <= 5000
Example 1:
Input: head = [1, 2, 3, 4, 5]
Output: [5, 4, 3, 2, 1]Example 2:
Input: head = [1, 2]
Output: [2, 1]Example 3:
Input: head = []
Output: []Solution
Below is my solution and some test cases. This solution has a linear time complexity O(n) and a linear space complexity O(n), where n is the length of the input list.