码迷,mamicode.com
首页 > 其他好文 > 详细

Leetcode Reverse Linked List II

时间:2014-06-25 23:36:53      阅读:291      评论:0      收藏:0      [点我收藏+]

标签:style   class   blog   code   ext   color   

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->NULLm = 2 and n = 4,

return 1->4->3->2->5->NULL.

Note:
Given mn satisfy the following condition:
1 ≤ m ≤ n ≤ length of list.

ListNode *reverseBetween(ListNode *head, int m, int n) {
    ListNode *newHead = new ListNode(-1);
    newHead->next = head;
    ListNode *p = head, *pre = newHead;
    int cnt = 0;
    while(cnt < m-1) {pre = p;p=p->next;cnt++;}
    ListNode *q = p;
    p=p->next;cnt++;
    while(cnt< n){
        ListNode *node = p->next;
        p->next=pre->next;
        pre->next = p;
        p = node;
        q->next = node;
        cnt++;
    }
    return newHead->next;
}

 

Leetcode Reverse Linked List II,布布扣,bubuko.com

Leetcode Reverse Linked List II

标签:style   class   blog   code   ext   color   

原文地址:http://www.cnblogs.com/xiongqiangcs/p/3804412.html

(0)
(0)
   
举报
评论 一句话评论(0
登录后才能评论!
© 2014 mamicode.com 版权所有  联系我们:gaon5@hotmail.com
迷上了代码!