Given the head of a singly linked list, reverse the list, and return the reversed list.
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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: [] ++ +
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Constraints:
+ +-
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- The number of nodes in the list is the range
[0, 5000].
+ -5000 <= Node.val <= 5000
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Follow up: A linked list can be reversed either iteratively or recursively. Could you implement both?
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