一个简单的链表程序
/******************************************************************************/
/* 作者: 神vLinux飘飘 */
/* bbs.bc-cn.net */
/* 时间:2005年1月13日 */
/* 版权没有，盗版不究 */
/******************************************************************************/
#include
/*数据结构*/
strUCt card
{
char name[30];
char tel[30];
char zip[255];
struct card *front_point;
struct card *next_point;
};
struct card *head_point; /*头节点*/
struct card *end_point; /*尾节点*/
struct card *now_point; /*当前节点,很多操作都是围绕这个节点来完成*/
/*命令函数区*/
void uppoint(); /*当前节点上移一条记录*/
void downpoint(); /*当前节点下移一条记录*/
void save(); /*保存文件*/
void new(); /*在当前节点之后创建一个新的记录,并把当前节点指向新记录*/
void ver(); /*显示版本号,无聊....*/
void del(); /*删除当前节点的记录*/
void list(); /*显示所有的记录*/
void point(); /*显示当前节点所指向的记录*/
void quit(); /*退出程序(推荐选项)*/
void find(); /*查找记录,并且把节点指向找到的记录.有两种查找方式(按名字,按电话)*/
void cls(); /*清屏*/
/*功能函数区*/
void load(); /*装载文件*/
void commandline(); /*命令行,你所有的指令都由它来理解,执行*/
void show(struct card *); /*打印记录*/
void error(int ); /*错误系统,好象显得有点多余*/
void trade(struct card*,struct card*); /*交换两个记录在链表中的位置uppoint和downpoint用*/
struct card *search(char *,int); /*查找记录*/
void main()
{
ver();
load();
commandline();
}
void commandline()
{
char command[100];
printf("Card Master!
Write by vlinux
");
for(;;)
{
printf("CMD:");
gets(command);
if( strcmp(command,"new")==0 ) new();
else if( strcmp(command,"del")==0 ) del();
else if( strcmp(command,"find")==0 ) find();
else if( strcmp(command,"list")==0 ) list();
else if( strcmp(command,"point")==0 ) point();
else if( strcmp(command,"quit")==0 ) quit();
else if( strcmp(command,"cls")==0 ) cls();
else if( strcmp(command,"ver")==0 ) ver();
else if( strcmp(command,"save")==0 ) save();
else if( strcmp(command,"uppoint")==0 ) uppoint();
else if( strcmp(command,"downpoint")==0)downpoint();
else error(0);
}
}
void show(struct card *show_point)
{
printf("
_______________________________
");
printf("NAME : %s
",show_point->name);
printf("TEL : %s
",show_point->tel);
printf("ZIP : %s",show_point->zip);
printf("
_______________________________
");
}
void list()
{
struct card *list_point;
int count=0;
if( head_point->next_point == end_point )
{
printf("This is an empty Card!
");
return;
}
list_point=head_point->next_point;
for(;list_point->next_point!=NULL;list_point=list_point->next_point)
{
show(list_point);
count++;
}
printf("Total %d
",count);
}
void point()
{
show(now_point);
}
void new()
{
struct card *new_point;
new_point=(struct card*)malloc(sizeof(struct card));
new_point->next_point=now_point->next_point;
new_point->front_point=now_point;
now_point->next_point=new_point;
now_point=new_point;
printf("Enter NAME:");
gets(new_point->name);
printf("Enter TEL:");
gets(new_point->tel);
printf("Enter ZIP:");
gets(new_point->zip);
printf("Creat a new card
");
show(new_point);
printf("
");
}
void find()
{
struct card *find_point;
char Words[255];
printf("FIND....
");
printf("Enter your search about? (name/tel) :");
gets(words);
if( strcmp(words,"name")== 0 )
{
printf("Enter NAME:");
gets(words);
find_point=search(words,0);
if( find_point==NULL )
{
error(1);
return;
}
else
{
show(find_point);
now_point=find_point;
return;
}
}
if( strcmp(words,"tel")== 0 )
{
printf("Enter TEL:");
gets(words);
find_point=search(words,1);
if( find_point==NULL )
{
error(1);
return;
}
else
{
show(find_point);
now_point=find_point;
return;
}
}
printf("Error!
");
}
struct card * search(char *words,int type)
{
struct card *search_point;
search_point=head_point->next_point;
if( type == 0 )
{
for(;search_point->next_point!=NULL;search_point=search_point->next_point)
{
if( strcmp(search_point->name,words) == 0 )
{
return search_point;
}
}
return NULL;
}
if( type == 1 )
{
for(;search_point->next_point!=NULL;search_point=search_point->next_point)
{
if( strcmp(search_point->tel,words) == 0 )
{
return search_point;
}
}
return NULL;
}
}
void quit()
{
char words[10];
printf("Quit,are you sure?(yes/no)");
gets(words);
if( (strcmp(words,"yes"))!=0 )
{
printf("Drop action!
");
return;
}
exit(0);
}
void error(int type)
{
if( type == 0)
{
printf("Bad command!
");
return;
}
if( type == 1)
{
printf("Find Nothing!
");
return;
}
}
void del()
{
struct card *temp_point;
char words[255];
if(head_point->next_point->next_point==NULL)
{
error(1);
return;
}
show(now_point);
printf("It will delete this card, are you sure?(yes/no) ");
gets(words);
if( strcmp(words,"yes")!=0 )
{
printf("drop this action!
");
return;
}
printf("Del the card:
");
temp_point=now_point->front_point;
now_point->next_point->front_point=now_point->front_point;
now_point->front_point->next_point=now_point->next_point;
free(now_point);
now_point=temp_point;
}
void cls()
{
int i;
for(i=0;i<60;i++)
printf("
");
}
void ver()
{
printf("
____________________________________________________________________________");
printf("
Build by vlinux");
printf("
@CopyRight");
printf("
GXDX.NN.GX.China");
printf("
----------------------------------------------------------------------------");
printf("
");
}
void load()
{
FILE *fp;
struct card *load_point;
struct card *temp_point;
if( (fp=fopen("cardsave.mmd","rb"))==NULL )
{
printf("Creat a new cardsave!
");
if( (fp=fopen("cardsave.mmd","wb"))==NULL)
{
printf("Sorry~Can not creat files!
");
return;
}
printf("ok!
");
fclose(fp);
}
head_point=(struct card*)malloc(sizeof(struct card));
end_point=(struct card*)malloc(sizeof(struct card));
head_point->front_point=NULL;
head_point->next_point=end_point;
end_point->front_point=head_point;
end_point->next_point=NULL;
strcpy(head_point->name,"HEAD");
strcpy(head_point->tel,"HEAD");
strcpy(head_point->zip,"HEAD");
strcpy(end_point->name,"END");
strcpy(end_point->tel,"END");
strcpy(end_point->zip,"END");
now_point=head_point;
while(!feof(fp))
{
load_point=(struct card*)malloc(sizeof(struct card));
fread(load_point,sizeof(struct card),1,fp);
load_point->next_point=now_point->next_point;
load_point->front_point=now_point;
now_point->next_point=load_point;
now_point=load_point;
}
fclose(fp);
temp_point=now_point->front_point;
now_point->next_point->front_point=now_point->front_point;
now_point->front_point->next_point=now_point->next_point;
free(now_point);
now_point=temp_point;
printf("Load files finished!
");
return;
}
void save()
{
FILE *fp;
struct card *save_point;
char words[10];
printf("It will change cardsave.mmd file,are you sure?(yes/no)");
gets(words);
if( (strcmp(words,"yes"))!= 0)
{
printf("Drop action!
");
return;
}
printf("Saving...
");
if( (fp=fopen("cardsave.mmd","wb"))==NULL )
{
printf("Can't save files!
");
return;
}
save_point=head_point->next_point;
for(;save_point->next_point!=NULL;save_point=save_point->next_point)
{
fwrite(save_point,sizeof(struct card),1,fp);
}
printf("Save finished!
");
}
void uppoint()
{
if( now_point->front_point==head_point )
{
printf("Sorry can not move TOP!
");
return;
}
printf("Trade cards:");
show(now_point);
show(now_point->front_point);
trade(now_point->front_point,now_point);
printf("Trade finished!
");
}
void downpoint()
{
if( now_point->next_point==end_point )
{
printf("Sorry can not move END!
");
return;
}
printf("Trade cards:");
show(now_point);
show(now_point->next_point);
trade(now_point,now_point->next_point);
printf("Trade finished!
");
}
void trade(struct card *a_point,struct card *b_point)
{
a_point->front_point->next_point=b_point;
b_point->next_point->front_point=a_point;
a_point->next_point=b_point->next_point;
b_point->front_point=a_point->front_point;
a_point->front_point=b_point;
b_point->next_point=a_point;
}
使用说明：
本程序采用的是双链表的结构，并且头链HEAD和尾链END是指定的，不能更改。
-----<记录1>----<记录2>---- ... ----<记录3>----
很多操作都是围绕now_point（当前节点）来进行的。
new 在当前节点后插入一个新的记录，并且把当前节点指向新记录；
del 删除当前节点的记录，当前节点自动指向前一个记录；
ver 显示版本号，没什么用，纯粹娱乐；
list 显示所有记录；
point 显示当前节点所指向的记录；
uppoint 当前节点往前移一条记录，不改变当前节点的指向；
downpoint当前节点往后移动一条记录，同样不改变当前节点的指向；
find 可以按照name或者tel来进行查找，假如找到，当前节点自动指向它；
cls 清屏；
quit 退出程序。
由于将近半年的时间没看C语言，而且又曾经误入学习编程的误区（跑去看Java），现在回来感到很多东西都忘光了。所以随便写写个代码看起来比较长的程序来练练手。
这个程序纯粹是娱乐所做，没什么实际意义。
当然，假如你把数据结构和new函数改改就可以变成图书馆治理系统或者是学生治理系统什么的。
由于这个程序是在半夜写的，所以写完之后第二天早上赶忙起来检查了一遍，重新写了中文注释。我想，既然printf("Hellow MM");都可以拿出来show show，那我的应该没问题吧~~
哦~还有一个重要的问题：
请大家帮我查查我的load函数的装载文件部分，
while(!feof(fp))
{
load_point=(struct card*)malloc(sizeof(struct card));
fread(load_point,sizeof(struct card),1,fp);
load_point->next_point=now_point->next_point;
load_point->front_point=now_point;
now_point->next_point=load_point;
now_point=load_point;
}
fclose(fp);
/*删除多余记录*/
temp_point=now_point->front_point;
now_point->next_point->front_point=now_point->front_point;
now_point->front_point->next_point=now_point->next_point;
free(now_point);
now_point=temp_point;
/**************/
它老是自己在装载完之后又多加了一条空记录进来，我想了半天都没想明白到底是怎么回事。所以只好在装载完之后又多加了 删除多余记录 的代码。真是无奈啊。请大家帮我分析分析。
