C语言,从文件中读取数据给结构体变量赋值,不知道哪里错了

#include
#include
#include
struct student {
int number;
}num;

int main()
{

struct student s1, *s2;
s2 = &s1;
FILE *fp = fopen("test.txt", "r");
fscanf(fp, "%d", s2->number);

return 0;

}

fscanf(fp, "%d", &(s2->number));

#if 1
#include

struct student {
int number;
}num;
int main()
{
struct student s1, *s2;
s2 = &s1;
FILE *f;
fopen_s(&f, "test.txt", "r");
fscanf_s(f, "%d", &(s2->number), 4);
printf("%d\n", s2->number);
return 0;
}
#endif