谁帮我看看这表链错在那里编译不了啊

#include <stdio.h>
#include <stdlib.h>
#include <malloc.h>
#define NULL 0
#define LEN sizeof(struct student)
struct student
{
long num;
float score;
struct student *next;
};
int n;/*n为全局变量，文件模块中各个函数均可使用它*/
struct student *creat(void)/*定义函数，此函数带回一个指向链表的指针*/
{
struct student *head;
struct strdent *p1,*p2;
n=0;
p1=p2=(struct student *)malloc(LEN);/*开辟一个新单元*/
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%5.1f\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");
return head;
}
p1=head;
while(num!=p1->num && p1->next!=NULL)/*若p1指向的不是首结点，并且后面还有结点*/
{
p2=p1;p1=p1->next;/*p1后移一个结点*/
}
if(num==p1->num)/*找到了*/
{
if(p1==head)head=p1->next;/*若p1指向的是首结点，把第二结点的地址赋予head*/
else p2->next=p1->next;/*否则将下一个结点地址赋给前一结点地址*/
printf("delete:%ld\n",num);
n=n-1;
}
else printf("%ld not been found!\n",num);/*找不到该节点*/
return(head);
}
struct student *insert(struct student *head,struct student *stud)
{
struct student *p0,*p1,*p2;
p1=head;/*使p1指向第一个结点*/
p0=stud;/*p0指向要插入的结点*/
if(head==NULL)/*原来的链表是空表*/
{
head=p0;
p0->next=NULL;/*使p0指向的结点为头结点*/
}
else
{
while((p0->num>p1->num)&&(p1->next!=NULL))
{
p2=p1;/*使p2指向刚才p1指向的结点*/
p1=p1->next;/*p1后移一个结点*/
}
if(p0->num<=p1->num)
{
if(head==p1) head=p0;/*插到原来第一个结点之前*/
else p2->next=p0;/*插到p2 指向的结点之后*/
p0->next=p1;
}
else
{
p1->next=p0;p0->next=NULL;/*插到最后的结点之后*/
}
}
n=n+1;/*结点数加1*/
return(head);
}
int main()
{
struct student *head,*stu;
long del_num;
printf("input recotds:\n");
head=creat();/*建立链表返回头指针*/
print(head);/*输出全局结点*/
printf("\ninput the deleted number:");
scanf("%ld",&del_num);/*输入要删除的学号*/
while(del_num!=0)
{
head=del(head,del_num);/**/
print(head);
printf("input the deletde 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);
prin(head);
printf("input the inserted tecord:");
stu=(struct student *)malloc(LEN);
scanf("%ld,%f",&stu->num,&stu->score);
}
system("pause");
return 0;
}