void insert() {
 printf("请输入学号:");
 scanf("%ld",&student[i].xuehao);
 
 printf("请输入姓名:");
 scanf("%s",student[i].name);
 
 printf("请输入班级:");
 scanf("%s",student[i].banji);
 
 printf("请输入上机时间:");
 scanf("%d:%d",&student[i].begin.hour,&student[i].begin.minute);
 i = i + 1;
 printf("人数：%d",i);
       j=i;
       save();
 printf("\n");  system("pause");
 system("cls");
}