#include<stdio.h>
#define NULL 0
struct student
{
    long num;
    float score;
    struct strdent * next;
};

void main ()
{
    struct student a, b, c, *head, *p;
    a.num = 10101;a.score = 89.5;
    b.num = 10103;b.score = 90;
    c.num = 10107;c.score = 89;
    head = &a;
    a.next = &b;
    b.next = &c;
    c.next = NULL;
    p = head;
    do
    {
        printf ("%ld %5.ld\n",p->num,p->score);
        p = p->next;
    }
    while (p != NULL);
}

printf ("%ld %5.ld\n",p->num,p->score);  - >   printf ("%ld %3.1f\n",p->num,p->score);

struct strdent * next;
 printf ("%ld %5.ld\n",p->num,p->score);
这两处错的太明显了．

谢谢了

p=p->next;
a.next = &b;
    b.next = &c;

转换错误，与指向的类型无关；转换要求 reinterpret_cast、C 样式转换或函数样式转换