leetcode61. 旋转链表

/**
 * Definition for singly-linked list.
 * struct ListNode {
 *     int val;
 *     ListNode *next;
 *     ListNode(int x) : val(x), next(NULL) {}
 * };
 */
class Solution {
public:
    ListNode* rotateRight(ListNode* head, int k) {
        if(head == nullptr || head->next == nullptr)
        {
            return head;
        }
        vector<int> v;
        while(head)
        {
            v.push_back(head->val);
            head = head->next;
        }
        vector<int> temp = v;
        for(int i = 0; i < temp.size(); i++)
        {
            v.push_back(temp[i]);
        }
        int len = k % temp.size();
        vector<int> res;
        for(int i = temp.size() - len; i < temp.size() - len + temp.size(); i++)
        {
            res.push_back(v[i]);
        }
        ListNode* r = new ListNode(0);
        ListNode* dummynode = r;
        for(int i = 0; i < res.size(); i++)
        {
            dummynode->val = res[i];
            if(i == res.size() - 1)
            {
                break;
            }
            dummynode->next = new ListNode(0);
            dummynode = dummynode->next;
        }
        return r;
    }
};