【LeetCode】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.

public class Solution {

    public ListNode reverseBetween(ListNode head, int m, int n) {

        if(m==n||m>n)

            return head;

        int len = n-m;

        ListNode root = head;

        m--;

        while(m!=0&&root!=null){

            root = root.next;

            m--;

        }

        ListNode cur = root;

        while(len!=0&&len>0){

            ListNode temp = cur;

            int i=len;

            while(i!=0){

                temp=temp.next;

                i--;

            }

int tempv = cur.val;

            cur.val=temp.val;

            temp.val=tempv;

            len-=2;

            cur=cur.next;

        }
return head;
}

}

【LeetCode】Reverse Linked List II,布布扣,bubuko.com