Reverse Linked List II


Reverse a linked list from position m to n. Do it in-place and in one-pass.
For example:
Given 1->2->3->4->5->NULL, m = 2 and n = 4,
return 1->4->3->2->5->NULL.
Note:
Given m, n satisfy the following condition:
1 <= m <= n <= length of list.
Solution: Record the position m-1, m, n, n+1. reverse between m and n, and let m-1 -> next = n, m -> next = n+1.

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