简单链表的实现.txt

[转贴]简单链表的实现.txt我刚学C不久,看到链表这就写了这个.给刚学C的朋友们,希望大家共同进步,也希望高手们也看看提出缺点和不足. 谢谢!

我刚学C不久,看到链表这就写了这个.给刚学C的朋友们,希望大家共同进步,也希望高手们也看看提出缺点和不足.
谢谢!
#include<stdio.h>
#include<malloc.h>
#include<stdlib.h>
////////链表结构体////////
struct chain
{
char data;
struct chain *next;
};
////////声明////////
int Menu();
struct chain *Create(void);
struct chain *Insert(struct chain *head);
struct chain *Del(struct chain *head);
void Free(struct chain *head);
void print(struct chain *head);
////////主函数////////
void main()
{
struct chain *top;
for (; ;)
{
  switch (Menu())
  {
  case 1:
   top=Create();
   print(top);
   printf("\n");
   break;
  case 2:
   top=Insert(top);
            print(top);
            printf("\n");
   break;
  case 3:
   top=Del(top);
            print(top);
            printf("\n");
   break;
  case 4:
   Free(top);
   exit(0);
  }
}
}
////////菜单函数////////
int Menu()
{
char s;
int num;
printf("1.建立链表\n");
    printf("2.插入元素\n");
printf("3.删除元素\n");
printf("4.退出\n");
do
{
  s=getchar();
  num=(int)s-48;
}while (num<0 || num>4);
return num;
}
////////建立链表////////
struct chain *Create(void)
{
struct chain *head,*tail,*p;
head=tail=NULL;
char ch;
printf("输入链表元素:");
    getchar();
while ((ch=getchar())!='\n')
{
  p=(struct chain *)malloc (sizeof(struct chain));
  p->data=ch;
  p->next=NULL;
  if (head==NULL)
  {
   head=tail=p;
  }
  else
  {
   tail=tail->next=p;
  }
}
return head;
}
////////插入函数////////
struct chain *Insert(struct chain *head)
{
struct chain *p,*q,*insert;
char c,d;
printf("输入插入元素位于之前数据:");
    getchar();
c=getchar();
printf("输入插入元素:");
getchar();
d=getchar();
    insert=(struct chain *)malloc (sizeof(struct chain));
insert->data=d;
if (head==NULL)
{
  head=insert;
  insert->next=NULL;
}
if (head->data==c)
{
  insert->next=head;
  head=insert;
}
else
{
  p=head;
  while ((p->data!=c) && (p->next!=NULL))
  {
   q=p;
   p=p->next;
  }
  if (p->data==c)
  {
   q->next=insert;
   insert->next=p;
  }
  else
  {
   p->next=insert;
   insert->next=NULL;
  }
}
return (head);
}
////////删除函数////////
struct chain *Del(struct chain *head)
{
struct chain *p=NULL,*q=NULL;
char del;
printf("输入要删除的数据:");
    getchar();
    del=getchar();
    if (head==NULL)
{
  printf("空链表\n");
}
else if (head->data==del)
{
  p=head;
  head=head->next;
}
else
{
  p=head;
  while ((p->data!=del) && (p->next!=NULL))
  {
   q=p;
   p=p->next;
  }
  if (p->data !=del)
  {
   printf("没有要删除的数据");
  }
  else
  {
   q->next=p->next;
   free(p);
  }
}
return (head);
}
////////输出函数////////
void print(struct chain *head)
{
while (head!=NULL)
{
  printf("%c",head->data);
  head=head->next;
}
}
////////释放内存////////
void Free(struct chain *head)
{
struct chain *p,*q;
p=head;
while (p!=NULL)
{
  q=p->next;
  free(p);
  p=q;
}
}