单链表逆转

 1 //递归方法逆转 单链表
 2 Node* RecReverseList(Node* head)
 3 {
 4     if(!head || !head->next)
 5     {
 6         return head;
 7     }
 8 
 9     Node *newhead = RecReverseList(head->next);
10     head->next->next = head;
11     head->next = NULL;
12     return newhead;
13 }
14 
15 //非递归方式逆转 单链表
16 Node* RecReverseList(Node* head)
17 {
18     if(!head || !head->next)
19     {
20         return head;
21     }
22     Node* p1 = head;
23     Node* p2  = p1->next;
24     head->next = NULL;
25 
26     while(p2)
27     {
28         p1 = p2;
29         p2 = p2->next;
30         p1->next = head;
31         head = p2;
32     }
33     return head;
34 }