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

    }
};