题目：（LinkedList）

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.

 

题解：

/** * Definition for singly-linked list. * public class ListNode { *     int val; *     ListNode next; *     ListNode(int x) { *         val = x; *         next = null; *     } * } */public class Solution {    public ListNode reverseBetween(ListNode head, int m, int n) {        ListNode fakeHead = new ListNode(0);        fakeHead.next = head ;                if(head==null||head.next==null)           return fakeHead.next;                   ListNode prev = fakeHead;        ListNode curr = null;        ListNode last = null;                for(int i=0; i