1 #include <stdio.h>
2 #include <stdlib.h>
3 #include <string.h>
4
5 struct node
6 {
7 int data;
8 struct node *pNext;
9 };
10
11 //新建node
12 struct node * create_node(int data)
13 {
14 struct node *p = (struct node *) malloc (sizeof(struct node));
15
16 if(NULL == p)
17 {
18 printf("malloc error!.\n");
19 return NULL;
20 }
21 memset(p, 0, sizeof(struct node));
22 p->data = data;
23 p->pNext = NULL;
24
25 return p;
26 }
27
28 //尾部插入
29 void insert_tail(struct node *pH, struct node *newp)
30 {
31 struct node * p = pH;
32 while(NULL != p->pNext)
33 {
34 p = p->pNext;
35 }
36 p->pNext = newp;
37 }
38
39 //头部插入
40 void insert_head(struct node * pH, struct node *newp)
41 {
42 newp->pNext = pH->pNext;
43 pH->pNext = newp;
44 }
45
46 //excluding header data
47 //不能打印头结点
48 void list_for_each_1(struct node *pH)
49 {
50 struct node *p = pH->pNext;
51 printf("------------begin------------\n");
52 while(NULL != p->pNext)
53 {
54 printf("node data : %d.\n", p->data);
55 p = p->pNext;
56 }
57 printf("node data : %d.\n", p->data);
58 printf("------------end------------\n");
59 }
60
61 //excluding header data version 2 simplify
62 //不能打印头结点，版本优化
63 void list_for_each_3(struct node *pH)
64 {
65 struct node *p = pH;
66 printf("------------begin------------\n");
67 while(NULL != p->pNext)
68 {
69 p = p->pNext;
70 printf("node data : %d.\n", p->data);
71 }
72 printf("------------end------------\n");
73 }
74
75 //including header data
76 //能打印头结点
77 int list_for_each_2(struct node *pH)
78 {
79 struct node *p = pH;
80 printf("------------begin------------\n");
81 if(NULL == p)
82 {
83 printf("nothing.\n");
84 return -1;
85 }
86 while(NULL != p->pNext)
87 {
88 printf("node data : %d.\n", p->data);
89 p = p->pNext;
90 }
91 printf("node data : %d.\n", p->data);
92 printf("------------end------------\n");
93 return 0;
94 }
95
96 //can not delete header node data
97 //不能删除头结点
98 int delete_node(struct node * pH, int data)
99 {
100 struct node *p = pH;
101 struct node *pPrev = NULL;
102 while(NULL != p->pNext)
103 {
104 pPrev = p;
105 p = p->pNext;
106 if(p->data == data)
107 {
108 if(NULL == p->pNext)
109 {
110 pPrev->pNext = NULL;
111 free(p);
112 }
113 else
114 {
115 pPrev->pNext = p->pNext;
116 free(p);
117 }
118 return 0;
119 }
120 }
121 printf("no node deleted.\n");
122 return -1;
123 }
124
125 //can delete all node including the tail node and header node
126 //能删除头结点和尾节点
127 struct node * delete_node_2(struct node * pH, int data)
128 {
129 struct node *p = pH;
130 struct node *pPrev = NULL;
131 pPrev = p;
132 while(NULL != p) //traserval to tail
133 {
134 if(p->data == data)
135 {
136 //delete header node
137 if(p->data == pH->data)
138 {
139 pH = p->pNext;
140 free(p);
141 printf("node %d deleted ok.\n",data);
142 return pH; //delete ok!
143 }
144 else
145 {
146 //delete tail node
147 if(NULL == p->pNext)
148 {
149 pPrev->pNext = NULL;
150 free(p);
151 }
152 else
153 {
154 pPrev->pNext = p->pNext;
155 free(p);
156 }
157 printf("node %d deleted ok.\n",data);
158 return pH;
159 }
160 printf("node %d deleted ok.\n",data);
161 }
162 pPrev = p;
163 p = p->pNext;
164 }
165 return pH;
166 }
167
168
169 int main()
170 {
171 struct node * pHeader = create_node(1);
172 printf("Hello world!\n");
173
174 insert_tail(pHeader, create_node(2));
175 insert_tail(pHeader, create_node(3));
176 insert_head(pHeader, create_node(4));
177 insert_head(pHeader, create_node(5));
178 list_for_each_2(pHeader);
179 pHeader = delete_node_2(pHeader, 3);
180 pHeader = delete_node_2(pHeader, 2);
181 pHeader = delete_node_2(pHeader, 5);
182 pHeader = delete_node_2(pHeader, 4);
183 pHeader = delete_node_2(pHeader, 1);
184 list_for_each_2(pHeader);
185 // printf("1 = %d\n",pHeader->data);
186 // printf("2 = %d\n",pHeader->pNext->data);
187 // printf("3 = %d\n",pHeader->pNext->pNext->data);
188 // printf("4 = %d\n",pHeader->pNext->pNext->pNext->data);
189 // printf("5 = %d\n",pHeader->pNext->pNext->pNext->pNext->data);
190
191 return 0;
192 }
