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.

/** * Definition for singly-linked list. * struct ListNode { *     int val; *     ListNode *next; *     ListNode(int x) : val(x), next(NULL) {} * }; */class Solution {public:    ListNode *reverseBetween(ListNode *head, int m, int n) {        ListNode *begin = head;        ListNode *temp;        for(int i = 1; i < m; i++)begin = begin->next;        temp = begin;        vector<int>a;        for(int i = m; i <= n; i++)        {            a.push_back(temp->val);            temp = temp->next;        }        temp = begin;        for(int i = m; i <= n; i++)        {            temp->val = a[n-i];            temp = temp->next;        }                return head;    }};