新人学习链表,该如何解决

新人学习链表
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

struct student
{
 int num;
 char name[30];
 struct student *next;
};

void create(struct student*p);

void display(struct student*p);

int main()
{
 struct student *head;
 head=(struct student*)malloc(sizeof(struct student));
 head->next=NULL;
 create(&head);
 display(&head); 
 system("pause");
 return 0;
}

void create(struct student*p)
{
 struct student*q;
 int num;
 char name[30];
 q=p;
 while(1)
 {
  printf("请输入学号:");
  scanf("%d",&num);
  if(num==0)
  {
  p->next=NULL;
  break;
  }
  printf("请输入姓名");
  scanf("%s",name);
  strcpy(p->name,name);
  p->num=num;
  q=(struct student*)malloc(sizeof(struct student));
  p->next=q;
  p=q;
  }
}

void display(struct student*p)
{
  while(p!=NULL)
  {
  printf("%d %s ",p->num,p->name);
  p=p->next;
  }
}
这个链表编译输出都通过了，就是会在最后输出一行垃圾值，不知道链表结尾怎么错了

[解决办法]
这明显不行，
create(&head);display(&head);改为create(head);display(head);并不是把指针的地址给函数

[解决办法]

C/C++ code

strcpy(p->name,name);  p->num=num;  q=(struct student*)malloc(sizeof(struct student));  p->next=q;  p=q;
[解决办法]
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

struct student
{
int num;
char name[30];
struct student *next;
};

struct student* create(struct student*p);

struct student* display(struct student*p);

int main()
{
struct student *head;
head=(struct student*)malloc(sizeof(struct student));
head->next=NULL;
head=create(head);
head=display(head); 
system("pause");
return 0;
}

struct student* create(struct student*p)
{
struct student *head=p;
struct student*q;
int num;
char name[30];
q=p;
while(1)
{
printf("请输入学号:");
scanf("%d",&num);
if(num==0)
{
p->next=NULL;
break;
}
printf("请输入姓名");
scanf("%s",name);
strcpy(p->name,name);
p->num=num;
q=(struct student*)malloc(sizeof(struct student));
p->next=q;
q->next=NULL;
p=q;
}
return head;
}

struct student* display(struct student*p)
{
struct student *head=p;
while(p->next!=NULL)
{
printf("%d %s ",p->num,p->name);
p=p->next;
}
return head;
}
[解决办法]
开始学习链表最好是在纸上画一画，各个指针的指向，多画几次就懂了