陡的反义词是什么呢:C 语言程序异常中断

这是一个链表程序，能对起进行建表，删除，添加等操作，编译正常，但在运行时会提示：scanf : floating point formats not linked
abnormal program termination
整个程序如下：
#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 * head;
struct student *p1,*p2;
n=0;
p1=p2=(struct student *) malloc(LEN);
scanf("%ld,%f",&p1->num,&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);
scanf("%ld%f",&p1->num,&p1->score);
}
p2->next=NULL;
return(head);
}

void print(struct student * head)
{
struct student * p;
printf("\nNow,these %d records are:\n",n);
p=head;
if(head!=NULL)
do
{
printf("%ld%5.2f\n",p->num,p->score);
p=p->next;
}
while(p!=NULL);
}

struct student * del(struct student * head,long num)
{
struct student *p1,*p2;
if(head==NULL)
{
printf("\nlist null!\n");
}
while(head!=NULL)
{
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:%ld\n",num);
n=n-1;
}
else
printf("%ld not been found !\n",num);
}
return(head);
}

struct student * insert(struct student * head,struct student * stud)
{
struct student *p0,*p1,*p2;
p1=head;
p0=stud;
if(head==NULL)
{
head=p0;
p0->next=NULL;
}
else
while((p0->num>p1->num) && (p1->next!=NULL))
{
p2=p1;
p1=p1->next;
}
if(p0->num<=p1->num)
{
if(head==p1)
head=p0;
else
p2->next=p0;
p0->next=p1;
}
else
{
p1->next=p0;p0->next=NULL;
}
n=n+1;
return(head);
}

main()
{
struct student * head,* stu;
long del_num;
printf("input records:\n");
head=creat();
print(head);
printf("\ninput the deleted number:");
scanf("%ld",&del_num);
while(del_num!=0)
{
head=del(head,del_num);
print(head);
printf("input the deleted number:");
scanf("%ld",&del_num);
}
printf("\ninput the inserted record:");
stu=(struct student *)malloc(LEN);
scanf("%ld,%f",&stu->num,&stu->score);
while(stu->num!=0)
{
head=insert(head,stu);
print(head);
printf("input the inserted record:");
stu=(struct student *)malloc(LEN);
scanf("%ld,%f",&stu->num,&stu->score);
}
}


chief_lfw:我看了你改的，但还是不行啊‘‘