C++反转单链表

/*
struct ListNode {
    int val;
    struct ListNode *next;
    ListNode(int x) :
            val(x), next(NULL) {
    }
};*/
class Solution {
public:
    ListNode* ReverseList(ListNode* pHead) {
        ListNode* pReversedHead = NULL;
        ListNode* pNode = pHead;
        ListNode* pPrev = NULL;
        while(pNode != NULL){
            ListNode* pNext = pNode->next;
            if(pNext == NULL){
                pReversedHead = pNode;
            }
            pNode->next = pPrev;
            pPrev = pNode;
            pNode = pNext;
        }
        return pReversedHead;
    }
};