学校要求用链表编一个学生成绩管理系统，我在第一步成绩输入和输出就出问题了，输入成绩时在输入number那输入0不结束while循环，连续输入0倒是可以结束while循环，但是在输出时就成了死循环。求教高手如何解决。程序可能运行下会更好解决吧。谢谢大家帮忙，第一次发帖，请多指教。
程序如下：
#include<stdio.h>
#include<malloc.h>
#include <string.h>
#define NULL 0
#define len sizeof(struct student)

struct student
{long num;
 char name[20];
 float msco;
 float csco;
 float esco;
 struct student *next;
};
 int n;
 struct student *creat(void)
{
 struct student *head;
 struct student *p1,*p2;
 n=0;
 p1=p2=(struct student *)malloc(len);
 printf("please input the number of the student:");
 scanf("%ld",&p1->num);
 printf("please input the name of the student:");
 scanf("%s",&p1->name);
 printf("please input the math of the student:");
 scanf("%f",&p1->msco);
 printf("please input the cprogram of the student:");
 scanf("%f",&p1->csco);
 printf("please input the english of the student:");
 scanf("%f",&p1->esco);
 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 input the number of the student:");
   scanf("%ld",&p1->num);
   printf("please input the name of the student:");
   scanf("%s",&p1->name);
   printf("please input the math of the student:");
   scanf("%f",&p1->csco);
   printf("please input the cprogram of the student:");
   scanf("%f",&p1->esco);
   printf("please input the english of the student:");
   scanf("%f",&p1->name);
  }
 p2->next=NULL;
 return(head);
}
void print(struct student *head)
{
 struct student *p;
 p=head;
 if(head!=NULL)
  do
   {printf("%d",p->num);
    printf("%s",p->name);
    printf("%f",p->msco);
    printf("%f",p->csco);
    printf("%f",p->esco);
   }while(p!=NULL);
}
main()
{
float arg,*point=&arg;
struct student *head;
head=creat();
print(head);
}

按你的修改后还是不对 不过还是谢谢你啊

能不能说清楚一点，我刚学没多久，看不懂你写的什么意思哦。非常感谢！

知道原因也修改了，非常感谢啊！！
但还有个问题想请教下，就是前面的这一段输入的问题，为什么我在num处输入0他还是不结束while循环呢？

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 input the number of the student:");
   scanf("%ld",&p1->num);
   printf("please input the name of the student:");
   scanf("%s",&p1->name);
   printf("please input the math of the student:");
   scanf("%f",&p1->csco);
   printf("please input the cprogram of the student:");
   scanf("%f",&p1->esco);
   printf("please input the english of the student:");
   scanf("%f",&p1->name);
  }
p2->next=NULL;
return(head);
}

现在的程序修改如下
前面的问题都已经解决，但是新问题又来了，输出的时候输出不完整（name项输不出来）且多输入几次还会产生乱码。
希望大家能帮帮我 不胜感谢！
#include<stdio.h>
#include<malloc.h>
#include <string.h>
#define NULL 0
#define len sizeof(struct student)
struct student
{long num;
 char name[20];
 float msco;
 float csco;
 float esco;
 struct student *next;
};
 int n;
 struct student *creat()
{
 struct student *head;
 struct student *p1,*p2;
 n=0;
 do
 {
   p1=(struct student *)malloc(len);
   printf("please input the number of the student:");
   scanf("%ld",&p1->num);
   if(p1->num==0)break;
   printf("please input the name of the student:");
   scanf("%s",&p1->name);
   printf("please input the math of the student:");
   scanf("%f",&p1->csco);
   printf("please input the cprogram of the student:");
   scanf("%f",&p1->esco);
   printf("please input the english of the student:");
   scanf("%f",&p1->name);
   n=n+1;
   if(n==1)head=p1;
   else p2->next=p1;
   p2=p1;
  }while(p1->num!=0);
 p2->next=NULL;
 return(head);
}
void print(struct student *head)
{
 struct student *p;
 p=head;
 if(head!=NULL)
  do
   {printf("%d",p->num);
    printf("%s",p->name);
    printf("%7.2f",p->msco);
    printf("%7.2f",p->csco);
    printf("%7.2f",p->esco);
    p=p->next;
   }while(p!=NULL);
}
main()
{
float arg,*point=&arg;
struct student *head;
head=creat();
print(head);
}

知道原因所在了，输入英语的我搞成输入名字了。再次谢谢大哥指导哦！