一楼给吧主

//借书卡操作
import java.util.Scanner;
public class JieShuKa{
String zhanghao,name;
int ID,yijie,yihuan;
int kejie=20;
void borrow(int cash){
if(kejie>=cash){
kejie=kejie-cash;
System.out.println("本次借书数为："+cash);
System.out.println("还可借书数为："+kejie);
}
}
void theReturn(int cash){
yihuan=yihuan+cash;
System.out.println("本次还书："+cash);
}
}
class BookCard extends JieShuKa{
void bookcard(String name,String zhanghao,int ID){
System.out.println("持卡人姓名："+name+"持卡人账号："+zhanghao+"身份证号："+ID);
}}
public class Card {
public static void main(String[] args){
String name,zhanghao;
int ID;
int s1,s2,s3;
Scanner ss=new Scanner(System.in);
System.out.println("请输入持卡人姓名：");
name=ss.nextLine();
System.out.println("请输入持卡人账号：");
zhanghao=ss.nextLine();
System.out.println("请输入持卡人身份证号：");
ID=ss.nextInt();
BookCard str1=new BookCard();
str1.bookcard(zhanghao, zhanghao, ID);
JieShuKa str2=new JieShuKa();
System.out.println("请输入本次借书数：");
s1=ss.nextInt();
str2.borrow(s1);
System.out.println("请输入本次还书数：");
s3=ss.nextInt();
str2.theReturn(s3);
}
}

//描述人类信息
public class Ren{
private String name;
String sex;
int age;
int weight;
public void Ren(String Name,String Sex,int Age,int Weight){
this.name=Name;
sex=Sex;
age=Age;
weight=Weight;
System.out.println("人类是高级动物");}
void walk(){
System.out.println("人类直立行走");}
void eat(String e){
System.out.println("人类喜欢吃"+ e);}
void show(){
System.out.println("我的名字叫"+name+",性别："+sex+",今年"+age+"岁了，"+"体重是"+weight+"kg。");
}
public class person{
public void main(String args[]){
Ren s=new Ren("王昊","男",21,60);
s.walk();
s.eat("肉");
s.show();
}
}
}

class staff{
private String name;
String sex;
public staff(){
}
void gongzi(){
System.out.println("都发放工资");
}
}
class worker extends staff{
double salary;
void workers(String e){
System.out.println("是否发放津贴："+e);
}
void gongzi(){
System.out.println("工人发放工资");
}
void showInfo(String name,String sex){
System.out.println("我是"+name+",性别"+sex);
}
}
class manager extends staff{
String transport;
void managers(String s){
System.out.println("是否配备交通工具："+s);
}
void gongzi(){
System.out.println("经理发放工资");
}
void showInfo(String name,String sex){
System.out.println("我是"+name+",性别"+sex);
}
}
public class Employee {
public static void main(String[] args){
worker a=new worker();
a.workers("是");
a.showInfo("张三","女");
a.gongzi();
manager b=new manager();
b.managers("是");
b.showInfo("李四","男");
b.gongzi();
}
}

public class meiqi {
double e,a;
double f;
double s;
void Mqds(){
System.out.println("上月煤气表读数："+e);
System.out.println("本月煤气表读数："+f);
}
void Mqjs(){
s=f-e;
System.out.println("本月用煤气数："+s);
}
void Mqfy(){
s=f-e;
a=s*2;
System.out.println("本月煤气费用："+a);
}
public static void main(String args[]){
meiqi c = new meiqi();
c.e=150;
c.f=300;
c.Mqds();
c.Mqjs();
c.Mqfy();
}
}