DataStructure_Algorithm_HandBook_PreForLeetCode

206. Reverse Linked List

Given the head of a singly linked list, reverse the list, and return the reversed list.

Example 1:

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Input: head = [1,2,3,4,5]
Output: [5,4,3,2,1]

Example 2:

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Input: head = [1,2]
Output: [2,1]

Example 3:

Input: head = []
Output: []

Constraints:

Follow up: A linked list can be reversed either iteratively or recursively. Could you implement both?

Solution:

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Code:

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