#include<stdio.h>
#include<stdlib.h>
#define LEN sizeof(struct Student)
struct Student
{long num;
 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);
 scanf("%ld,%5.1f",&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);
}
void main()
{struct Student *head;
 head=creat();
 print(head);
}

以上的程序有问题莫？
我输入数据之后，按下空格，然后就按键盘就输入不了数据了，运行其他程序的时候没问题，就是运行这个程序出现这种情况，求解答