头插法实现反转

struct ListNode {
	int val;
	struct ListNode *next;
	ListNode(int x) :
			val(x), next(NULL) {
	}
};*/
class Solution {
public:
    ListNode* ReverseList(ListNode* pHead) {
        if(!pHead){
            return NULL;
        }
        ListNode* head_New=NULL,*cur=pHead,*temp=NULL;
        while(cur){
            temp=new ListNode(cur->val);
            temp->next=head_New;
            head_New=temp;
            cur=cur->next;
        }
        return head_New;
    }
};