#include<stdio.h>
#include<stdlib.h>
#define LEN sizeof(struct Student)
struct Student { long num; char name[20]; int age; float score; struct Student *next; };
int n;
struct Student *creat()
{ struct Student*head;
struct Student *p1,*p2;
n=0;
p1=p2=(struct Student*)malloc(LEN);
printf("Please enter the student num\t");
scanf("%d",&p1->num);
if (p1->num==0)
return head=NULL;
printf("Please enter the student name\t"); scanf("%s",p1->name);
printf("Please enter the student age\t"); scanf("%d",&p1->age);
printf("Please enter the student score\t"); scanf("%f",&p1->score);
head=NULL;
while(p1->num!=0)
{
n=n+1;
if(n==1)head=p1;
else p2->next=p1;
p2=p1;
p1=(struct Student*)malloc(LEN);
printf("Please enter the student num\t");
scanf("%d",&p1->num);
if (p1->num==0){ p2->next=NULL; return head; }
printf("Please enter the student name\t");
scanf("%s",p1->name);
printf("Please enter the student age\t");
scanf("%d",&p1->age);
printf("Please enter the student score\t");
scanf("%f",&p1->score); }
}
void print(struct Student *head)
{
struct Student *p;
printf("\nNow,These %d records are:\n",n);
p=head;
if(head!=NULL) do
{printf("%d\t%s\t%d\t%.1lf\n",p->num,p->name,p->age,p->score); p=p->next; }
while(p!=NULL);
}
struct Student *insert(struct Student *head)
{
struct Student *p1,*p2,*p3;
p2=head;
p1=(struct Student*)malloc(LEN);
printf("Now you can insert new student\n");
printf("Please enter the student num\t");
scanf("%d",&p1->num);
printf("Please enter the student name\t");
scanf("%s",p1->name);
printf("Please enter the student age\t");
scanf("%d",&p1->age);
printf("Please enter the student score\t");
scanf("%f",&p1->score);
if(head==NULL) { head=p1; p1->next=NULL; }
else
{
while( (p1->num>p2->num)&&(p2->next!=NULL)) { p3=p2; p2=p2->next; }
if(p1->num<p2->num)
{
if(head==p2) { head=p1; p1->next=p2; }
else { p3->next=p1; p1->next=p2; }
}
else
{ p2->next=p1; p1->next=NULL; }
}
n=n+1;
return head; }
struct Student *del(struct Student *head,long num)
{ struct Student *p1,*p2;
if(head==NULL)
{ printf("\nlist null\n"); return head; }
p1=head;
while(num!=p1->num && p1->next!=NULL)
{ p2=p1; p1=p1->next; }
if(num==p1->num)
{ if(p1==head) head=p1->next;
else p2->next=p1->next;
printf("delete :%d\n",num);
n-=1;
free(p1); }
else printf("num not found\n");
return head;
}
void main()
{ struct Student *head; int num;
head=creat(); print(head);
head=insert(head); print(head);
printf("enter delete number\n"); scanf("%d",&num);
head=del(head,num); print(head);
}