引发的异常: 0xC0000005: 写入位置 0xCDCDCDCD 时发生访问冲突。

Question

#include
#include
#include

#define LEN sizeof(struct student)

struct student *creat();
void print(struct student *head);

struct student
{
int num;
float score;
struct student *next;
};

int n;

void main()
{
struct student *stu;

stu = creat();
print( stu );

printf("\n\n");
system("pause");

}

struct student *creat()
{
struct student *head;
struct student *p1, *p2;

p1 = p2 = (struct student *)malloc(LEN);

printf("please enter the num:\n");
scanf_s("%d", p1->num,sizeof(p1->num));
printf("please enter the score:\n");
scanf_s("%f", p1->score,sizeof(p1->score));

head = NULL;
n = 0;

while (p1->num)
{
    n++;
    if (n == 1)
    {
        head = p1;
    }
    else
    {
        p2->next = p1;
    }
    p2 = p1;
    p1 = (struct student *)malloc(LEN);

    printf("please enter the num:\n");
    scanf_s("%d", p1->num, sizeof(p1->num));
    printf("please enter the score:\n");
    scanf_s("%f", p1->score, sizeof(p1->score));
}
p2->next = NULL;

return head;

}

void print(struct student *head)
{
struct student *p;
p = head;
while (p->next)
{
printf("学号： %d 分数： %f\n", p->num, p->score);
p = p->next;
}
}

运行环境为vs2017，win10 64位。在运行到第一个scanf_s处是报的错：
0x0F86742E (ucrtbased.dll)处(位于 lianbiao.exe 中)引发的异常: 0xC0000005: 写入位置 0xCDCDCDCD 时发生访问冲突。

看见有人说是引用了未初始化的内存，那么怎么初始化呢？试过calloc函数，报错如下：

求大佬教教，感激不尽!

Answer 1

所有的scanf函数后面的变量都应该取地址，例如：
将：

scanf_s("%d", p1->num, sizeof(p1->num));

改为：

scanf_s("%d", &p1->num, sizeof(p1->num));