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Java面向对象 - 封装、继承和多态的综合练习
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泰迪male brown波斯猫male2.5预期输出：名称：泰迪，性别：male，颜色：brown，汪汪叫
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泰迪吃骨头！名称：波斯猫，性别：male，体重：2.5kg，喵喵叫 波斯猫吃鱼！
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package case1;
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import java.util.Scanner;
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public class Task1 {
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public static void main(String[] args) {
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Scanner sc = new Scanner(System.in);
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String dogName = sc.next();
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String dogSex = sc.next();
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String dogColor = sc.next();
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String catName = sc.next();
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String catSex = sc.next();
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double catWeight = sc.nextDouble();
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Dog chs=new Dog();
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chs.setDog(dogName,dogSex,dogColor);
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chs.talk();
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chs.eat();
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Cat jq=new Cat();
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jq.setCat(catName,catSex,catWeight);
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jq.talk();
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jq.eat();} }
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abstract class Pet {
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String name;
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String sex;
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public void setPet(String name,String sex){
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this.name=name;
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this.sex=sex;
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}
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abstract void talk();
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abstract void eat();
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}
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class Dog extends Pet {
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String color;
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public void setDog(String name,String sex,String color){
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this.color=color;
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super.setPet(name,sex); }
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public void talk(){
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System.out.println("名称："+this.name+"，性别："+this.sex+"，颜色："+this.color+"，汪汪叫"); }
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public void eat(){
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System.out.println(this.name+"吃骨头！"); }}
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class Cat extends Pet {
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double weight;
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public void setCat(String name,String sex,double weight){
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this.weight=weight;
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super.setPet(name,sex); }
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public void talk(){
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System.out.println("名称："+this.name+"，性别："+this.sex+"，体重："+this.weight+"kg，喵喵叫"); }
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public void eat(){
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System.out.println(this.name+"吃鱼！"); }}
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张三 男 20 史蒂文 男 22
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预期输出：
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姓名：张三，性别：男，年龄：20，我是中国人，我喜欢吃饭!
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姓名：史蒂文，性别：男，年龄：22，我是英国人，我喜欢吃三明治!
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张三在练习太极拳!
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史蒂文在练习骑马！
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package case2;
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import java.util.Scanner;
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public class Task2 {
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public static void main(String[] args) {
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Scanner sc = new Scanner(System.in);
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String cName = sc.next();
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String cSex = sc.next();
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int cAge = sc.nextInt();
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String eName = sc.next();
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String eSex = sc.next();
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int eAge = sc.nextInt();
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Person st=new Chinese(cName,cSex,cAge);
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showEat(st);
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English chs=new English(eName,eSex,eAge);
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showEat(chs);
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Chinese st2=(Chinese)st;
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st2.shadowBoxing();
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English chs2=(English)chs;
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chs2.horseRiding(); }
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public static void showEat(Person p){
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p.eat(); }}
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abstract class Person {
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abstract void eat();
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String name;
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String sex;
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int age;
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public void setPerson(String name,String sex,int age){
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this.name=name;
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this.sex=sex;
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this.age=age;
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}}
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class Chinese extends Person {
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public void eat(){
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System.out.println("姓名："+this.name+"，性别："+this.sex+"，年龄："+this.age+"，我是中国人，我喜欢吃饭！"); }
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public Chinese(String name,String sex,int age){
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super.setPerson(name,sex,age); }
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public void shadowBoxing(){
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System.out.println(this.name+"在练习太极拳！"); }}
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class English extends Person {
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public void eat(){
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System.out.println("姓名："+this.name+"，性别："+this.sex+"，年龄："+this.age+"，我是英国人，我喜欢吃三明治！"); }
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public English(String name,String sex,int age){
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super.setPerson(name,sex,age); }
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void horseRiding(){
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System.out.println(this.name+"在练习骑马！"); }}
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张继科 30 易建联 31 刘国梁 42 杜锋 37
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预期输出：
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张继科---30
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人都是要睡觉的
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乒乓球运动员吃大白菜，喝小米粥
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乒乓球运动员学习如何发球和接球
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乒乓球运动员说英语
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----------------
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易建联---31
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人都是要睡觉的
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篮球运动员吃牛肉，喝牛奶
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篮球运动员学习如何运球和投篮
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----------------
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刘国梁---42
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人都是要睡觉的
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乒乓球教练吃小白菜，喝大米粥
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乒乓球教练教如何发球和接球
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乒乓球教练说英语
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----------------
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杜锋---37
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人都是要睡觉的
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篮球教练吃羊肉，喝羊奶
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篮球教练教如何运球和投篮
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----------------
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package case3;
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import java.util.Scanner;
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public class Task3 {
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public static void main(String[] args) {
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Scanner sc = new Scanner(System.in);
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String pppName = sc.next();
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int pppAge = sc.nextInt();
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String bpName = sc.next();
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int bpAge = sc.nextInt();
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String ppcName = sc.next();
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int ppcAge = sc.nextInt();
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String bcName = sc.next();
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int bcAge = sc.nextInt();
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PingPangPlayer ppp=new PingPangPlayer(pppName,pppAge);
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System.out.println(pppName+"---"+pppAge);
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ppp.sleep();
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ppp.eat();
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ppp.study();
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ppp.speak();
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BasketballPlayer bp=new BasketballPlayer(bpName,bpAge);
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System.out.println(bpName+"---"+bpAge);
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bp.sleep();
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bp.eat();
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bp.study();
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PingPangCoach ppc=new PingPangCoach(ppcName,ppcAge);
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System.out.println(ppcName+"---"+ppcAge);
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ppc.sleep();
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ppc.eat();
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ppc.teach();
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ppc.speak();
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BasketballCoach bc=new BasketballCoach(bcName,bcAge);
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System.out.println(bcName+"---"+bcAge);
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bc.sleep();
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bc.eat();
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bc.teach();
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System.out.println("----------------"); }}
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interface SpeakEnglish {
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abstract void speak();}
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abstract class Person {
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String name;
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int age;
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public Person(String name,int age){
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this.name=name;
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this.age=age; }
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public void sleep(){
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System.out.println("人都是要睡觉的"); }
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abstract void eat();}
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abstract class Player extends Person {
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public Player(String name,int age){
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super(name,age); }
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abstract void study();}
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abstract class Coach extends Person {
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public Coach(String name,int age){
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super(name,age); }
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abstract void teach();}
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class PingPangPlayer extends Player implements SpeakEnglish {
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public PingPangPlayer(String name,int age){
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super(name,age); }
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public void eat(){
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System.out.println("乒乓球运动员吃大白菜，喝小米粥"); }
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public void study(){
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System.out.println("乒乓球运动员学习如何发球和接球"); }
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public void speak(){
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System.out.println("乒乓球运动员说英语"); }}
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class BasketballPlayer extends Player {
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public BasketballPlayer(String name,int age){
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super(name,age); }
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public void eat(){
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System.out.println("篮球运动员吃牛肉，喝牛奶"); }
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public void study(){
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System.out.println("篮球运动员学习如何运球和投篮"); }}
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class PingPangCoach extends Coach implements SpeakEnglish {
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public PingPangCoach(String name,int age){
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super(name,age); }
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public void eat(){
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System.out.println("乒乓球教练吃小白菜，喝大米粥"); }
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public void teach(){
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System.out.println("乒乓球教练教如何发球和接球"); }
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public void speak(){
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System.out.println("乒乓球教练说英语"); }}
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class BasketballCoach extends Coach {
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public BasketballCoach(String name,int age){
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super(name,age); }
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public void eat(){
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System.out.println("篮球教练吃羊肉，喝羊奶"); }
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public void teach(){
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System.out.println("篮球教练教如何运球和投篮"); }}
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package case3;
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import java.util.Scanner;
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public class Task3 {
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public static void main(String[] args) {
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Scanner sc = new Scanner(System.in);
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String pppName = sc.next();
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int pppAge = sc.nextInt();
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String bpName = sc.next();
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int bpAge = sc.nextInt();
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String ppcName = sc.next();
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int ppcAge = sc.nextInt();
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String bcName = sc.next();
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int bcAge = sc.nextInt();
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PingPangPlayer ppp=new PingPangPlayer(pppName,pppAge);
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System.out.println(pppName+"---"+pppAge);
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ppp.sleep();
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ppp.eat();
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ppp.study();
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ppp.speak();
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BasketballPlayer bp=new BasketballPlayer(bpName,bpAge);
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System.out.println(bpName+"---"+bpAge);
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bp.sleep();
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bp.eat();
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bp.study();
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PingPangCoach ppc=new PingPangCoach(ppcName,ppcAge);
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System.out.println(ppcName+"---"+ppcAge);
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ppc.sleep();
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ppc.eat();
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ppc.teach();
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ppc.speak();
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BasketballCoach bc=new BasketballCoach(bcName,bcAge);
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System.out.println(bcName+"---"+bcAge);
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bc.sleep();
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bc.eat();
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bc.teach();
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System.out.println("----------------"); }}
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interface SpeakEnglish {
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abstract void speak();}
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abstract class Person {
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String name;
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int age;
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public Person(String name,int age){
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this.name=name;
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this.age=age; }
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public void sleep(){
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System.out.println("人都是要睡觉的")} }
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abstract void eat();}
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abstract class Player extends Person {
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public Player(String name,int age){
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super(name,age); }
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abstract void study();}
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abstract class Coach extends Person {
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public Coach(String name,int age){
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super(name,age); }
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abstract void teach();}
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class PingPangPlayer extends Player implements SpeakEnglish {
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public PingPangPlayer(String name,int age){
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super(name,age); }
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public void eat(){
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System.out.println("乒乓球运动员吃大白菜，喝小米粥"); }
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public void study(){
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System.out.println("乒乓球运动员学习如何发球和接球"); }
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public void speak(){
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System.out.println("乒乓球运动员说英语"); }}
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class BasketballPlayer extends Player {
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public BasketballPlayer(String name,int age){
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super(name,age); }
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public void eat(){
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System.out.println("篮球运动员吃牛肉，喝牛奶"); }
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public void study(){
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System.out.println("篮球运动员学习如何运球和投篮"); }}
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class PingPangCoach extends Coach implements SpeakEnglish {
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public PingPangCoach(String name,int age){
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super(name,age); }
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public void eat(){
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System.out.println("乒乓球教练吃小白菜，喝大米粥"); }
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public void teach(){
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System.out.println("乒乓球教练教如何发球和接球"); }
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public void speak(){
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System.out.println("乒乓球教练说英语"); }
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/********* end *********/
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}
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class BasketballCoach extends Coach {
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/********* begin *********/
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public BasketballCoach(String name,int age){
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super(name,age);
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}
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public void eat(){
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System.out.println("篮球教练吃羊肉，喝羊奶");
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}
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public void teach(){
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System.out.println("篮球教练教如何运球和投篮");
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}
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/********* end *********/
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}
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Java面向对象 - 封装、继承和多态
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我是：张三，今年：18岁
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package case1;
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public class TestPersonDemo {
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public static void main(String[] args) {
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/********* begin *********/
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// 声明并实例化一Person对象p
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Person p =new Person();
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p.setName("张三") ;
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p.setAge(18) ;
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p.talk();
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}
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// 给p中的属性赋值
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// 调用Person类中的talk()方法
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/********* end *********/
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}
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// 在这里定义Person类
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class Person {
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/********* begin *********/
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private String name;
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private int age;
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/********* end *********/
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public String getName() {
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return name;
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}
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public void setName(String name) {
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this.name = name;
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}
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public int getAge() {
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return age;
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}
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public void setAge(int age) {
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this.age = age;
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}
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public void talk(){
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System.out.println("我是："+name+"，今年："+age+"岁");
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}
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}
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测试输入：无
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预期输出：
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|
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大花猫喵喵叫
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大花猫吃鱼
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大花猫6岁
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大黑狗汪汪叫
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大黑狗吃骨头
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大黑狗8岁
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package case2;
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public class extendsTest {
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public static void main(String args[]) {
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// 实例化一个Cat对象，设置属性name和age，调用voice()和eat()方法，再打印出名字和年龄信息
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/********* begin *********/
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Cat a =new Cat("大花猫",6);
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a.voice ("大花猫");
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a.eat ("大花猫");
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System.out.println(a.getName()+a.getAge()+"岁");
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/********* end *********/
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// 实例化一个Dog对象，设置属性name和age，调用voice()和eat()方法，再打印出名字和年龄信息
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|
/********* begin *********/
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|
|
Dog b = new Dog("大黑狗",8);
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b.voice ("大黑狗");
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b.eat ("大黑狗");
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System.out.println(b.getName()+b.getAge()+"岁");
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/********* end *********/
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}
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}
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|
|
|
|
class Animal {
|
|
|
/********* begin *********/
|
|
|
private String name;
|
|
|
private int age;
|
|
|
Animal(String name,int age){
|
|
|
this.name = name;
|
|
|
this.age = age;
|
|
|
}
|
|
|
/********* end *********/
|
|
|
public String getName() {
|
|
|
return name;
|
|
|
}
|
|
|
public void setName(String name) {
|
|
|
this.name = name;
|
|
|
}
|
|
|
public int getAge() {
|
|
|
return age;
|
|
|
}
|
|
|
public void setAge(int age) {
|
|
|
this.age = age;
|
|
|
}
|
|
|
|
|
|
/********* end *********/
|
|
|
|
|
|
}
|
|
|
|
|
|
class Cat extends Animal {
|
|
|
// 定义Cat类的voice()和eat()方法
|
|
|
/********* begin *********/
|
|
|
Cat(String name,int age){
|
|
|
super(name,age);
|
|
|
}
|
|
|
void voice(String name){
|
|
|
|
|
|
|
|
|
System.out.println(name+"喵喵叫");
|
|
|
}
|
|
|
void eat(String name){
|
|
|
System.out.println(name+"吃鱼");
|
|
|
} /********* end *********/
|
|
|
}
|
|
|
|
|
|
class Dog extends Animal {
|
|
|
// 定义Dog类的voice()和eat()方法
|
|
|
/********* begin *********/
|
|
|
Dog(String name,int age){
|
|
|
super(name,age);}
|
|
|
void voice(String name){
|
|
|
System.out.println(name+"汪汪叫");
|
|
|
}
|
|
|
void eat(String name){
|
|
|
System.out.println(name+"吃骨头");
|
|
|
}
|
|
|
/********* end *********/
|
|
|
}
|
|
|
测试输入：无
|
|
|
预期输出：
|
|
|
姓名：张三，年龄：18，学校：哈佛大学
|
|
|
package case3;
|
|
|
|
|
|
public class superTest {
|
|
|
public static void main(String[] args) {
|
|
|
// 实例化一个Student类的对象s，为Student对象s中的school赋值，打印输出信息
|
|
|
/********* begin *********/
|
|
|
Student s=new Student();
|
|
|
s.name="张三";
|
|
|
s.age=18;
|
|
|
s.school="哈佛大学";
|
|
|
|
|
|
s.b();
|
|
|
/********* end *********/
|
|
|
}
|
|
|
}
|
|
|
|
|
|
class Person {
|
|
|
/********* begin *********/
|
|
|
String name;
|
|
|
int age;
|
|
|
public void a(){
|
|
|
System.out.print("姓名："+name+"，"+"年龄："+age+"，");}
|
|
|
/********* end *********/
|
|
|
}
|
|
|
|
|
|
class Student extends Person {
|
|
|
/********* begin *********/
|
|
|
String school;
|
|
|
void b(){
|
|
|
super.a();
|
|
|
System.out.print("学校："+school);}
|
|
|
/********* end *********/
|
|
|
}
|
|
|
测试输入： 无
|
|
|
预期输出：
|
|
|
我是：张三，今年：18岁，我在哈佛大学上学
|
|
|
package case4;
|
|
|
|
|
|
public class overridingTest {
|
|
|
public static void main(String[] args) {
|
|
|
// 实例化子类对象s，调用talk()方法打印信息
|
|
|
/********* begin *********/
|
|
|
|
|
|
/********* end *********/
|
|
|
|
|
|
}
|
|
|
}
|
|
|
|
|
|
class Person {
|
|
|
/********* begin *********/
|
|
|
|
|
|
/********* end *********/
|
|
|
}
|
|
|
|
|
|
class Student extends Person {
|
|
|
/********* begin *********/
|
|
|
|
|
|
/********* end *********/
|
|
|
}
|
|
|
测试输入： 无
|
|
|
预期输出：
|
|
|
学生——>姓名：张三，年龄：20，职业：学生！
|
|
|
工人——>姓名：李四，年龄：30，职业：工人！
|
|
|
package case5;
|
|
|
|
|
|
public class abstractTest {
|
|
|
public static void main(String[] args) {
|
|
|
/********* begin *********/
|
|
|
// 分别实例化Student类与Worker类的对象，并调用各自构造方法初始化类属性。
|
|
|
Student s =new Student("张三",20,"学生");
|
|
|
Worker w =new Worker("李四",30,"工人");
|
|
|
s.talk();
|
|
|
w.talk();
|
|
|
// 分别调用各自类中被复写的talk()方法 打印信息。
|
|
|
|
|
|
/********* end *********/
|
|
|
|
|
|
}
|
|
|
}
|
|
|
|
|
|
// 声明一个名为Person的抽象类，在Person中声明了三个属性name age occupation和一个抽象方法——talk()。
|
|
|
abstract class Person {
|
|
|
/********* begin *********/
|
|
|
String name;
|
|
|
int age;
|
|
|
String occupation;
|
|
|
public abstract void talk();
|
|
|
|
|
|
/********* end *********/
|
|
|
}
|
|
|
|
|
|
// Student类继承自Person类，添加带三个参数的构造方法，复写talk()方法 返回姓名、年龄和职业信息
|
|
|
class Student extends Person {
|
|
|
/********* begin *********/
|
|
|
Student(String name,int age ,String occupation)
|
|
|
{
|
|
|
this.name=name;
|
|
|
this.age=age;
|
|
|
this.occupation=occupation;
|
|
|
}
|
|
|
public void talk(){
|
|
|
System.out.println("学生——>姓名："+name+"，年龄："+age+"，职业："+occupation+"！");
|
|
|
}
|
|
|
/********* end *********/
|
|
|
}
|
|
|
|
|
|
// Worker类继承自Person类，添加带三个参数的构造方法，复写talk()方法 返回姓名、年龄和职业信息
|
|
|
class Worker extends Person {
|
|
|
/********* begin *********/
|
|
|
Worker(String name ,int age ,String occupation)
|
|
|
{
|
|
|
this.name=name;
|
|
|
this.age=age;
|
|
|
this.occupation=occupation;
|
|
|
}
|
|
|
public void talk()
|
|
|
{
|
|
|
System.out.println("工人——>姓名："+name+"，年龄："+age+"，职业："+occupation+"！");
|
|
|
}
|
|
|
/********* end *********/
|
|
|
|
|
|
}
|
|
|
测试输入：无
|
|
|
预期输出：
|
|
|
speedlimit=120
|
|
|
running safely with 100kmph
|
|
|
running safely with 100kmph
|
|
|
package case6;
|
|
|
|
|
|
public class finalTest {
|
|
|
public static void main(String args[]) {
|
|
|
Bike1 obj = new Bike1();
|
|
|
obj.run();
|
|
|
|
|
|
Honda honda = new Honda();
|
|
|
honda.run();
|
|
|
|
|
|
Yamaha yamaha = new Yamaha();
|
|
|
yamaha.run();
|
|
|
}
|
|
|
}
|
|
|
//不可以修改 final 变量的值
|
|
|
// final方法,不可以重写
|
|
|
//// 不可以扩展 final 类
|
|
|
//请在此添加你的代码
|
|
|
/********** Begin *********/
|
|
|
class Bike1 {
|
|
|
int speedlimit = 90;
|
|
|
|
|
|
void run() {
|
|
|
speedlimit = 120;
|
|
|
System.out.println("speedlimit=120");
|
|
|
}
|
|
|
|
|
|
}
|
|
|
|
|
|
class Bike2 {
|
|
|
void run() {
|
|
|
System.out.println("running");
|
|
|
}
|
|
|
}
|
|
|
|
|
|
class Honda extends Bike2 {
|
|
|
void run() {
|
|
|
System.out.println("running safely with 100kmph");
|
|
|
}
|
|
|
|
|
|
}
|
|
|
|
|
|
class Bike3 {
|
|
|
}
|
|
|
|
|
|
class Yamaha extends Bike3 {
|
|
|
void run() {
|
|
|
System.out.println("running safely with 100kmph");
|
|
|
}
|
|
|
|
|
|
}
|
|
|
/********** End **********/
|
|
|
测试输入：无
|
|
|
预期输出：
|
|
|
学生——>姓名：张三，年龄：18，职业：学生！
|
|
|
package case7;
|
|
|
|
|
|
public class interfaceTest {
|
|
|
public static void main(String[] args) {
|
|
|
// 实例化一Student的对象s，并调用talk()方法，打印信息
|
|
|
/********* begin *********/
|
|
|
Student s =new Student();
|
|
|
s.talk();
|
|
|
/********* end *********/
|
|
|
|
|
|
}
|
|
|
}
|
|
|
|
|
|
// 声明一个Person接口，并在里面声明三个常量：name、age和occupation，并分别赋值，声明一抽象方法talk()
|
|
|
interface Person {
|
|
|
/********* begin *********/
|
|
|
String name="张三";
|
|
|
int age=18;
|
|
|
String occupation="学生";
|
|
|
/********* end *********/
|
|
|
}
|
|
|
|
|
|
// Student类继承自Person类 复写talk()方法返回姓名、年龄和职业信息
|
|
|
class Student implements Person {
|
|
|
/********* begin *********/
|
|
|
public void talk(){
|
|
|
System.out.println("学生——>姓名："+name+"，年龄："+age+"，职业："+occupation+"！");
|
|
|
}
|
|
|
/********* end *********/
|
|
|
}
|
|
|
测试输入：无
|
|
|
预期输出：
|
|
|
eating bread...
|
|
|
eating rat...
|
|
|
eating meat...
|
|
|
package case8;
|
|
|
|
|
|
public class TestPolymorphism {
|
|
|
public static void main(String[] args) {
|
|
|
// 以多态方式分别实例化子类对象并调用eat()方法
|
|
|
/********* begin *********/
|
|
|
Dog dog = new Dog();
|
|
|
Cat cat = new Cat();
|
|
|
Lion lion = new Lion();
|
|
|
dog.eat();
|
|
|
cat.eat();
|
|
|
lion.eat();
|
|
|
/********* end *********/
|
|
|
}
|
|
|
}
|
|
|
|
|
|
// Animal类中定义eat()方法
|
|
|
class Animal {
|
|
|
/********* begin *********/
|
|
|
public void eat(){};
|
|
|
/********* end *********/
|
|
|
}
|
|
|
|
|
|
// Dog类继承Animal类 复写eat()方法
|
|
|
class Dog extends Animal {
|
|
|
/********* begin *********/
|
|
|
public void eat(){
|
|
|
System.out.println("eating bread...");
|
|
|
}
|
|
|
/********* end *********/
|
|
|
}
|
|
|
|
|
|
// Cat类继承Animal类 复写eat()方法
|
|
|
class Cat extends Animal {
|
|
|
/********* begin *********/
|
|
|
public void eat(){
|
|
|
System.out.println("eating rat...");
|
|
|
}
|
|
|
/********* end *********/
|
|
|
}
|
|
|
|
|
|
// Lion类继承Animal类 复写eat()方法
|
|
|
class Lion extends Animal {
|
|
|
/********* begin *********/
|
|
|
public void eat(){
|
|
|
System.out.println("eating meat...");
|
|
|
}
|
|
|
/********* end *********/
|
|
|
}
|
|
|
|
|
|
Java面向对象 - 类与对象
|
|
|
测试输入：无
|
|
|
|
|
|
预期输出：使用中文冒号
|
|
|
名字：五花肉，毛色：棕色，品种：阿拉斯加
|
|
|
啃骨头
|
|
|
叼着骨头跑
|
|
|
package step1;
|
|
|
|
|
|
public class Test {
|
|
|
public static void main(String[] args) {
|
|
|
/********** Begin **********/
|
|
|
Dog wuhuarou = new Dog();//创建Dog对象
|
|
|
wuhuarou.name = "五花肉";
|
|
|
wuhuarou.color = "棕色";
|
|
|
wuhuarou.variety = "阿拉斯加";
|
|
|
//设置Dog对象的属性
|
|
|
//输出小狗的属性
|
|
|
System.out.println("名字：" + wuhuarou.name + "，毛色：" +wuhuarou.color + "，品种：" + wuhuarou.variety );
|
|
|
wuhuarou.eat();
|
|
|
wuhuarou.run();
|
|
|
//调用方法
|
|
|
/********** End **********/
|
|
|
}
|
|
|
}
|
|
|
//在这里定义Dog类
|
|
|
/********** Begin **********/
|
|
|
class Dog{
|
|
|
String name;
|
|
|
String color;
|
|
|
String variety;
|
|
|
public void eat(){
|
|
|
System.out.println("啃骨头"); }
|
|
|
public void run(){
|
|
|
System.out.println("叼着骨头跑"); }}
|
|
|
测试输入：张富贵，未知
|
|
|
预期输出：
|
|
|
一个人被创建了
|
|
|
姓名：张富贵，性别：未知，被创建了
|
|
|
package step2;
|
|
|
import java.util.Scanner;
|
|
|
public class Test {
|
|
|
public static void main(String[] args) {
|
|
|
Scanner sc = new Scanner(System.in);
|
|
|
String name = sc.next();
|
|
|
String sex = sc.next();
|
|
|
/********** Begin **********/
|
|
|
//分别使用两种构造器来创建Person对象
|
|
|
Person sut = new Person();
|
|
|
Person sut1 = new Person(name,sex);
|
|
|
/********** End **********/}}
|
|
|
|
|
|
//创建Person对象，并创建两种构造方法
|
|
|
/********** Begin **********/
|
|
|
class Person{
|
|
|
public Person(){
|
|
|
System.out.println("一个人被创建了"); }
|
|
|
public Person(String stuname,String stusex){
|
|
|
System.out.println("姓名："+stuname+"，性别："+stusex+"，被创建了"); }}
|
|
|
测试输入：
|
|
|
baby，45，女
|
|
|
预期输出：
|
|
|
name：baby
|
|
|
age：45
|
|
|
sex：女
|
|
|
package step3;
|
|
|
import java.util.Scanner;
|
|
|
public class Test {
|
|
|
public static void main(String[] args) {
|
|
|
Scanner sc = new Scanner(System.in);
|
|
|
String name = sc.next();
|
|
|
int age = sc.nextInt();
|
|
|
String sex = sc.next();
|
|
|
Person p = new Person(name,age,sex);
|
|
|
p.display();}}
|
|
|
class Person{
|
|
|
String name = "张三";
|
|
|
int age = 18;
|
|
|
String sex = "男";
|
|
|
/********** Begin **********/
|
|
|
public Person(String name,int age,String sex){
|
|
|
this.age = age;
|
|
|
this.name = name;
|
|
|
this.sex = sex;}
|
|
|
public Person(int age){
|
|
|
this.age = age;}
|
|
|
public void display(){
|
|
|
System.out.println("name：" + name);
|
|
|
System.out.println("age：" + age);
|
|
|
System.out.println("sex：" + sex); }
|
|
|
}
|
|
|
/********** End **********/
|
|
|
测试输入：
|
|
|
牛肉，3，true
|
|
|
预期输出：
|
|
|
面码：牛肉，粉的份量：3两，是否带汤：true
|
|
|
面码：牛肉，粉的份量：3两，是否带汤：false
|
|
|
面码：酸辣，粉的份量：2两，是否带汤：true
|
|
|
测试输入：
|
|
|
三鲜，1，true
|
|
|
预期输出：
|
|
|
面码：三鲜，粉的份量：1两，是否带汤：true
|
|
|
面码：三鲜，粉的份量：1两，是否带汤：false
|
|
|
面码：酸辣，粉的份量：2两，是否带汤：true
|
|
|
package step4;
|
|
|
import java.util.Scanner;
|
|
|
public class Test {
|
|
|
public static void main(String[] args) {
|
|
|
Scanner sc = new Scanner(System.in);
|
|
|
String theMa = sc.next();
|
|
|
int quantity = sc.nextInt();
|
|
|
boolean likeSoup = sc.nextBoolean();
|
|
|
/********** Begin **********/
|
|
|
WuMingFen f1 = new WuMingFen(theMa,quantity,likeSoup);//使用三个参数的构造方法创建WuMingFen对象 取名 f1
|
|
|
WuMingFen f2= new WuMingFen(theMa,quantity);//使用两个参数的构造方法创建WuMingFen对象 取名 f2
|
|
|
WuMingFen f3 = new WuMingFen();//使用无参构造方法创建WuMingFen对象 取名 f3
|
|
|
f1.check();//分别调用三个类的 check方法
|
|
|
/********** End **********/
|
|
|
}
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|
}
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package step4;//在这里添加包名 step4
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|
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|
//创建类 添加属性和方法
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public class WuMingFen{
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|
String TheMa;
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|
int quantity;
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|
boolean likeSoup;
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|
public WuMingFen(String TheMa,int quantity,boolean likeSoup){
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this.TheMa = TheMa;
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|
this.quantity = quantity;
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|
this.likeSoup = likeSoup;
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}
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|
public WuMingFen(String TheMa,int quantity){
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|
this.TheMa = TheMa;
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|
this.quantity = quantity;
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|
likeSoup = true;
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|
}
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public WuMingFen(){
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|
likeSoup = false;
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|
}
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public void check(){
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System.out.println("面码："+TheMa+"，粉的份量："+quantity+"两，是否带汤："+likeSoup);
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|
likeSoup = false;
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|
System.out.println("面码："+TheMa+"，粉的份量："+quantity+"两，是否带汤："+likeSoup);
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likeSoup = true;
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|
System.out.println("面码：酸辣，粉的份量：2两，是否带汤："+likeSoup);
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}
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}
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|
|
|
|
|
hello educoder
|
|
|
我叫楚留香
|
|
|
我喜欢在educoder上学习java
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|
|
package step5;
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|
|
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|
public class Test {
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|
/********** Begin **********/
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|
|
static String name = "楚留香";
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|
|
|
|
|
static{
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|
System.out.println("hello educoder");
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|
|
}
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|
|
public static void main(String[] args) {
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|
System.out.println("我叫"+name);
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|
|
study();
|
|
|
}
|
|
|
|
|
|
public static void study(){
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|
|
System.out.println("我喜欢在educoder上学习java");
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}
|
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/********** End **********/
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|
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}
|
|
|
数组进阶
|
|
|
|
|
|
预期输入：6，9，5，8，0，2，6
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|
|
预期输出：[0, 2, 5, 6, 8, 9]
|
|
|
|
|
|
预期输入：4，3，12，13，0
|
|
|
预期输出：[0, 3, 12, 13]
|
|
|
package step5;
|
|
|
|
|
|
import java.util.Arrays;
|
|
|
import java.util.Scanner;
|
|
|
|
|
|
public class HelloWorld {
|
|
|
|
|
|
public static void main(String[] args) {
|
|
|
Scanner sc = new Scanner(System.in);
|
|
|
//动态创建数组
|
|
|
int[] arr = new int[sc.nextInt()];
|
|
|
for(int i = 0 ; i< arr.length ; i++){
|
|
|
arr[i] = sc.nextInt();
|
|
|
}
|
|
|
/********** Begin **********/
|
|
|
for(int i=0;i<arr.length;i++){
|
|
|
for(int j=0;j<arr.length-i-1;j++){
|
|
|
if(arr[j]>arr[j+1]){
|
|
|
int temp=arr[j];
|
|
|
arr[j]=arr[j+1];
|
|
|
arr[j+1]=temp;
|
|
|
}
|
|
|
}
|
|
|
}
|
|
|
System.out.println(Arrays.toString(arr));
|
|
|
/********** End **********/
|
|
|
}
|
|
|
}
|
|
|
我会对你的程序进行测试；
|
|
|
预期输入：6，6，5，0，2，8，9
|
|
|
预期输出：[9, 8, 6, 5, 2, 0]
|
|
|
|
|
|
预期输入：4，3，12，1，13
|
|
|
预期输出：[13, 12, 3, 1]
|
|
|
package step4;
|
|
|
|
|
|
import java.util.Arrays;
|
|
|
import java.util.Scanner;
|
|
|
|
|
|
public class HelloWorld {
|
|
|
|
|
|
public static void main(String[] args) {
|
|
|
Scanner sc = new Scanner(System.in);
|
|
|
//动态创建数组
|
|
|
int[] arr = new int[sc.nextInt()];
|
|
|
for(int i = 0 ; i< arr.length ; i++){
|
|
|
arr[i] = sc.nextInt();
|
|
|
}
|
|
|
/********** Begin **********/
|
|
|
int max=0;
|
|
|
int ch=-1;
|
|
|
int[] a=new int[arr.length];
|
|
|
for(int i=0;i<arr.length;i++){
|
|
|
for(int j=0;j<arr.length;j++){
|
|
|
if(arr[j]>max){
|
|
|
max=arr[j];
|
|
|
ch=j;
|
|
|
}
|
|
|
}
|
|
|
arr[ch]=0;
|
|
|
a[i]=max;
|
|
|
max=-1;
|
|
|
ch=-1;
|
|
|
}
|
|
|
System.out.println(Arrays.toString(a));
|
|
|
/********** End **********/
|
|
|
}
|
|
|
}
|
|
|
测试输入：3，5
|
|
|
预期输出：
|
|
|
5
|
|
|
3
|
|
|
测试输入：4,2
|
|
|
预期输出：
|
|
|
2
|
|
|
4
|
|
|
package step3;
|
|
|
|
|
|
import java.util.Scanner;
|
|
|
|
|
|
public class HelloWorld {
|
|
|
|
|
|
public static void main(String[] args) {
|
|
|
Scanner sc = new Scanner(System.in);
|
|
|
int a = sc.nextInt();
|
|
|
int b = sc.nextInt();
|
|
|
/********** Begin **********/
|
|
|
//将a的值赋给b b的值赋给a
|
|
|
int t=a;
|
|
|
a=b;
|
|
|
b=t;
|
|
|
/********** End **********/
|
|
|
System.out.println(a);
|
|
|
System.out.println(b);
|
|
|
}
|
|
|
}
|
|
|
测试输入：张三
|
|
|
预期输出：张三在数组的第1个位置
|
|
|
|
|
|
测试输入：张富贵
|
|
|
预期输出：张富贵在数组的第5个位置
|
|
|
package step2;
|
|
|
import java.util.Scanner;
|
|
|
public class HelloWorld {
|
|
|
public static void main(String[] args) {
|
|
|
Scanner sc = new Scanner(System.in);
|
|
|
//str为要查找的字符串
|
|
|
String str = sc.next();
|
|
|
/********** Begin **********/
|
|
|
//创建数组 arr 给数组赋值 {"张三","张三丰","张无忌","王二麻子","张富贵"}
|
|
|
String[] arr = {"张三","张三丰","张无忌","王二麻子","张富贵"};
|
|
|
for(int i=0;i<5;i++){
|
|
|
if(str.equals(arr[i])){
|
|
|
System.out.println( str+ "在数组的第" + (i+1) + "个位置" );
|
|
|
}
|
|
|
}
|
|
|
/********** End **********/
|
|
|
}
|
|
|
}
|
|
|
测试输入：1，3，12
|
|
|
预期输出：
|
|
|
1
|
|
|
3
|
|
|
12
|
|
|
测试输入：2，13，11
|
|
|
预期输出：
|
|
|
2
|
|
|
13
|
|
|
11
|
|
|
package step1;
|
|
|
import java.util.Scanner;
|
|
|
public class HelloWorld {
|
|
|
public static void main(String[] args) {
|
|
|
//动态构建arr1
|
|
|
int[] arr1 = new int[3];
|
|
|
Scanner sc = new Scanner(System.in);
|
|
|
for(int i = 0 ; i< arr1.length ; i++){
|
|
|
arr1[i] = sc.nextInt();
|
|
|
}
|
|
|
/********** Begin **********/
|
|
|
//创建数组arr2
|
|
|
int[]arr2=new int[3];
|
|
|
|
|
|
//使用for循环将arr1的数据复制给arr2
|
|
|
for(int i=0;i<3;i++){
|
|
|
arr2[i]=arr1[i];
|
|
|
}
|
|
|
//输出arr2
|
|
|
for(int i=0;i<3;i++){
|
|
|
System.out.println(arr2[i]);
|
|
|
}
|
|
|
/********** End **********/
|
|
|
}
|
|
|
}
|
|
|
|
