这是我个人写的一个学生管理系统，这是我仅仅用来练手的代码，要知道链表可是你在面试过程中最大机率会考到的，我是陆续从单向链表入门，然后采用双向链表写的代码！如有BUG，请指正，让我们
共同进步！
1 #include<stdio.h>
2 #include<malloc.h>
3 #include<string.h>
4 struct student
5 {
6 int id;
7 char name[100];
8 int age;
9 int sex;
10 int class_num;
11 struct student *next;
12 struct student *pr;
13 };
14 typedef struct student link;
15 link *head;
16 int insert()
17 {
18 link *newnode;
19 newnode = (link *)malloc(sizeof(struct student));
20 link *temp_head = head;
21 printf("请输入学生ID：
");
22 scanf("%d",&newnode->id);
23 printf("请输入学生姓名：
");
24 scanf("%s",newnode->name);
25 printf("请输入学生年龄:
");
26 scanf("%d",&newnode->age);
27 printf("请输入学生性别0(代表男 1代表女):
");
28 scanf("%d",&newnode->sex);
29 if((newnode->sex == 0|| newnode->sex == 1) == 0)
30 {
31 printf("input is fail!
");
32 scanf("%d",&newnode->sex);
33 }
34 printf("请输入学生的班级号码：
");
35 scanf("%d",&newnode->class_num);
36 newnode->next = NULL;
37 newnode->pr = NULL;
38 if(temp_head->next == NULL)
39 {
40 temp_head->next = newnode;
41 newnode->pr = temp_head;
42 newnode->next = NULL;
43 return 0;
44 }
45 int flag = 0;
46 while(temp_head->next != NULL)
47 {
48 if(newnode->id < temp_head->next->id)
49 {
50 newnode->next = temp_head->next;
51 newnode->pr = temp_head;
52 temp_head->next = newnode;
53 newnode->next->pr = newnode;
54 flag = 1;
55 break;
56 }
57 temp_head = temp_head->next;
58 }
59 if(flag == 0)
60 {
61 temp_head->next = newnode;
62 newnode->next = NULL;
63 newnode->pr = temp_head;
64 }
65 return 0;
66 }
67 int input()
68 {
69 char num[100];
70 scanf("%s",num);
71 if(strcmp(num,"insert") == 0)
72 {
73 return 1;
74 }
75 else if(strcmp(num,"delete") == 0)
76 {
77 return 2;
78 }
79 else if(strcmp(num,"display") == 0)
80 {
81 return 3;
82 }
83 else if(strcmp(num,"exit") == 0)
84 {
85 return 4;
86 }
87 else
88 {
89 return 0;
90 }
91 }
92 int display(int id)
93 {
94 link *temp_head = head;
95 int flag = 0;
96 if(temp_head->next == NULL)
97 {
98 printf("没有输入学生信息：
");
99 return 0;
100 }
101 while(temp_head != NULL)
102 {
103 if(temp_head->id == id)
104 {
105 printf("id = %d
name = %s
age = %d
sex = %d
class_num = %d
",temp_head->id,temp_head->name,temp_head->age,temp_head->sex,temp_head->class_num);
106 flag = 1;
107 break;
108 }
109 temp_head = temp_head->next;
110 }
111 if(flag == 0)
112 {
113 printf("查无此人！
");
114 }
115 return 0;
116 }
117 int delete(int id)
118 {
119 link *temp_head = head;
120 int flag;
121 if(temp_head->next == NULL)
122 {
123 printf("学生内容为空，无法删除
");
124 return 0;
125 }
126 while(temp_head != NULL)
127 {
128 if(temp_head->id == id)
129 {
130 if(temp_head->next == NULL)
131 {
132 temp_head->pr->next = NULL;
133 flag = 1;
134 break;
135 }
136 else
137 {
138 temp_head->pr->next = temp_head->next;
139 temp_head->next->pr = temp_head->pr;
140 flag = 1;
141 break;
142 }
143 }
144 temp_head = temp_head->next;
145
146 }
147 if(flag == 1)
148 {
149 printf("删除成功!
");
150 }
151 else
152 {
153 printf("删除失败!
");
154 }
155 return 0;
156 }
157 int main()
158 {
159 int pid;
160 int id;
161 int class_num;
162 head = (link *)malloc(sizeof(struct student));
163 head->next = NULL;
164 head->pr = NULL;
165 printf("/****************************
");
166 printf(" 欢迎使用学生管理系统
");
167 printf(" 输入insert添加学生信息
");
168 printf(" 输入delete删除学生信息
");
169 printf(" 输入display查看学生信息
");
170 printf(" 输入exit退出程序
");
171 printf("*************************/
");
172 printf("请输入命令！
");
173 pid = input();
174 while(pid != 4)
175 {
176 switch(pid)
177 {
178 case 1 :
179 insert();
180 break;
181 case 2 :
182 printf("请输入要删除的学生ID：
");
183 scanf("%d",&id);
184 delete(id);
185 break;
186 case 3 :
187 printf("请输入要显示的学生ID：
");
188 scanf("%d",&id);
189 display(id);
190 break;
191 case 0 :
192 printf("输入的命令有误，请重新输入：
");
193 break;
194 case 4 :
195 break;
196 }
197 printf("请输入命令！
");
198 pid = input();
199 }
200 printf("该程序结束！
");
201 return 0;
202 }