//链表的操作
#include<stdio.h>
#include<malloc.h>
#define NULL 0
#define LEN sizeof(struct student)
struct student
{
long num;
float score;
struct student *next;
};//结点
int n;//存放结点个数
struct student *creat()//创建链表
{
struct student *head;//头指针
struct student *p1,*p2;
n=0;
head=NULL;
p1=p2=(struct student*)malloc(LEN);//分配存储空间
printf("input num,score:\n");
scanf("%ld,%f",&p1->num,&p1->score);
while(p1->num!=0)
{
n=n+1;
if(n==1)//第一个结点
head=p1;
else
{
p2->next=p1;
p2=p1;
}
p1=(struct student*)malloc(LEN);
printf("input num&&score:\n");
scanf("%ld,%f",&p1->num,&p1->score);
}
p2->next=NULL;
return head;//返回头指针
}
void print(struct student *head)//链表输出
{
struct student*p;
printf("\nNow,these %d records are:\n",n);
p=head;
if(head!=NULL)
while(p!=NULL)
{
printf("%ld\t%5.2f\n",p->num,p->score);
p=p->next;
}
}
struct student *del(struct student *head,long num)//链表的删除操作
{
struct student *p1,*p2;
if(head==NULL)//空链表
{
printf("\nListLink is null\n");
goto end;
}
p1=head;
while(num!=p1->num&&p1->next!=NULL)//查找要删除的结点,p1指向要删除的结点,p2指向要删除的结点的前一个结点
{
p2=p1;
p1=p1->next;
}
if(num==p1->num)
{
if(p1==head)//要删除的结点是第一个结点
head=p1->next;
else
p2->next=p1->next;
printf("delete %ld is succeed\n",num);
n=n-1;
}
else
printf("%ld not been found!\n",num);
end:
return head;
}
struct student *insert(struct student *head,struct student *stud)//链表的插入操作
{
struct student *p0,*p1,*p2;//p1存放插入位置的后一个结点,p2存放插入位置的前一个结点
p1=head;
p0=stud;//要插入的结点
if(head==NULL)//若链表为空链表
{
head=p0;
p0->next=NULL;
}
else
{
while((p0->num>p1->num)&&(p1->next!=NULL))//查找要插入的位置
{
p2=p1;
p1=p1->next;
}
if(p0->num<=p1->num)
{
if(head==p1)//插入位置为第一个结点,表头
head=p0;
else
p2->next=p0;
p0->next=p1;
}
else
{
p1->next=p0;//插入位置为表尾,
p0->next=NULL;
}
}
n=n+1;
return head;
}
void main()
{
struct student *head,*stu;
long del_num;
printf("input records:\n");
head=creat();//创建链表
print(head);
printf("\ninput the delete number:");
scanf("%ld",&del_num);
while(del_num!=0)//删除结点
{
head=del(head,del_num);
print(head);
printf("\ninput the delete number:");
scanf("%ld",&del_num);
}
printf("\ninput insert record:");
stu=(struct student*)malloc(LEN);
scanf("%ld,%f",&stu->num,&stu->score);
while(stu->num!=0)//插入结点
{
head=insert(head,stu);
print(head);
printf("\ninput insert record:");
stu=(struct student*)malloc(LEN);
scanf("%ld,%f",&stu->num,&stu->score);
}
}