61. Rotate List

Total Accepted: 69038  Total Submissions: 300765  Difficulty: Medium

Given a list, rotate the list to the right by k places, where k is non-negative.

For example:
Given 1->2->3->4->5->NULL and k = 2,
return 4->5->1->2->3->NULL.

Subscribe to see which companies asked this question

Hide Tags
  Linked List Two Pointers
Hide Similar Problems
  (E) Rotate Array

分析:

具体分析见代码,比较简单!

/**
 * Definition for singly-linked list.
 * struct ListNode {
 *     int val;
 *     ListNode *next;
 *     ListNode(int x) : val(x), next(NULL) {}
 * };
 */
//1,首先获取链表的长度,再根据k计算正序的新链表头
//2,建立连接
class Solution {
public:
    ListNode* rotateRight(ListNode* head, int k) {
        if(head==NULL || k==0)
            return head;
        int len=0;
        ListNode* pmove=head;
        ListNode* pend=NULL;
        ListNode* pnewhead=NULL;
        //1,获取链表长度
        while(pmove)
        {
            len++;
            pend=pmove;//记录尾节点
            pmove=pmove->next;
        }
        
        //2,找到新头的位置
        k=k%len;//取余
        if(k==0)
            return head;
        int nlen=len-k;
        pmove=head;
        while(--nlen)
            pmove=pmove->next;
       //3,建立连接
        pnewhead=pmove->next;
        pmove->next=NULL;
        pend->next=head;
        return pnewhead;
    }
};



注:本博文为EbowTang原创,后续可能继续更新本文。如果转载,请务必复制本条信息!

原文地址:http://blog.csdn.net/ebowtang/article/details/51422358

原作者博客:http://blog.csdn.net/ebowtang

本博客LeetCode题解索引:http://blog.csdn.net/ebowtang/article/details/50668895

你可能感兴趣的:(LeetCode,C++,技术,面试,遍历)