/*
struct ListNode {
	int val;
	struct ListNode *next;
	ListNode(int x) :
			val(x), next(NULL) {
	}
};*/
class Solution {
public:
	
    ListNode* ReverseList(ListNode* pHead) {
		ListNode* head = new ListNode(-1);
		while(pHead){
			auto tmp = pHead->next;
			pHead->next = head->next;
			head->next = pHead;
			pHead = tmp;
		}
		return head->next;
    }
};