开张了

中午蛋疼，再做一遍华为面试题，顺便立帖严重BS下面试那天自己写的作答！

很简单的代码，没有注释。

struct listNode 
 2 {
 3 int a;
 4     listNode * pNext;
 5 };
 6 
 7 listNode* makeList(int len)
 8 {
 9     listNode* pCreator  = NULL;
10     listNode* pRoller = (listNode*)malloc(sizeof(listNode));
11     listNode* pHead   = pRoller;
12     pHead->a =0;
13     pHead->pNext = NULL;
14 
15 for (int i=1; i<len; ++i)
16     {
17         pCreator = (listNode*)malloc(sizeof(listNode));
18         pCreator->a=i;
19         pCreator->pNext = NULL;
20         pRoller->pNext  = pCreator;
21         pRoller = pCreator;
22     }
23 
24 return pHead;
25 }
26 
27  void freeList(listNode* pHead)
28 {
29     listNode* pPrev=pHead;
30     listNode* pNext=NULL;
31 
32 while (pPrev != NULL)
33     {
34         pNext = pPrev->pNext;
35         free(pPrev);
36         pPrev = pNext;
37     }
38 }
39 
40 void printList(listNode* pHead)
41 {
42 while (pHead!=NULL)
43     {
44         printf("%d\n", pHead->a);
45         pHead = pHead->pNext;
46     }
47 }
48 
49 void reverseList(listNode** pHead)
50 {
51     listNode* pPrev = NULL;
52     listNode* pNext = NULL;
53     listNode* pCurr = NULL;
54 
55 if ((*pHead)==NULL || (*pHead)->pNext==NULL)
56     {
57 return;
58     }
59 
60     pPrev =*pHead;
61     pCurr = pPrev->pNext;
62     pPrev->pNext = NULL;//尾置空
63 
64 while (pCurr!=NULL && pCurr->pNext!=NULL)
65     {
66         pNext = pCurr->pNext;
67         pCurr->pNext = pPrev;
68         pPrev = pCurr;
69         pCurr = pNext;
70     }
71 
72     pCurr->pNext = pPrev;
73 *pHead = pCurr;
74 }
75 
76 int main()
77 {
78     listNode * head = makeList(15);
79     printList(head);
80 reverseList(&head);
81     printList(head);
82     freeList(head);
83     head = NULL;
84 return0;
85 }