将若干学生的档案放存在一个文件中，并显示其内容。

供参考：

#include<stdio.h>
struct student
{
     int  num;
     char name[10];
     int  age;
};

struct student stu[3]={{001,"Li Mei",18},
                       {002,"Ji Hua",19},
                       {003,"Sun Hao",18}};

void main()
{
    struct student *p;
    FILE  *fp;
    int   i;
    if((fp=fopen("stu_list","wb"))==NULL)
    {
        printf("cannot open file\n");
        return;
    }
    for(p=stu;p<stu+3;p++)
        fwrite(p,sizeof(struct student),1,fp);
    fclose(fp);
    
    fp = fopen("stu_list","rb");
    printf("No.    Name     age\n");
    for(i=1;i<=3;i++)
    {
        fread(p,sizeof(struct student),1,fp);
        printf("%-4d %-10s %-4d\n",p->num,p->name,p->age);
    }
    fclose(fp);
}