#include "stdio.h"
#include "malloc.h"
#define NULL 0
#define Len sizeof(struct student)
struct student
{long num;
 float score;
 struct student *next;
};
int n;
struct student *creat(void)
{struct student *p1,*p2,*head;
    n=0;    
p1=p2=(struct student *)malloc(Len);
scanf("%ld,%f",&p1->num,&p1->score);//scanf 得到的值只赋给p1->num,什么原因？
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);        
scanf("%ld,%f",&p1->num,&p1->score);
}
p2->next=NULL;
return(head);
}
void print(struct student *head)
{   struct student *p;
    p=head;
    if(head!=NULL)
    do
    {printf("a=%ld,b=%f",p->num,p->score);
    p=p->next;
    }while(p!=NULL);
    }
main()
{struct student *a;
 a=creat();
 print(a);
    }

见图片