명품 자바 프로그래밍(개정4판) 제 6장 실습문제

[1번]

class MyPoint{
	private int x,y;
	public MyPoint(int x,int y) {
		this.x=x;
		this.y=y;
	}
	public String toString() {
		return "Point("+x+","+y+")";
	}
	public boolean equals(MyPoint p) {
		return this.x==p.x&&this.y==p.y;
	}
}

public class p0601 {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		MyPoint p=new MyPoint(3,50);
		MyPoint q=new MyPoint(4,50);
		System.out.println(p);
		if(p.equals(q)) {
			System.out.println("같은 점");
		}
		else {
			System.out.println("다른 점");
		}
	}

}

---

[2번]

class Circle{
	private int x,y,r;
	public Circle(int x,int y,int r) {
		this.x=x;
		this.y=y;
		this.r=r;
	}
	public String toString() {
		return "Circle("+x+","+y+")반지름"+r;
	}
	public boolean equals(Circle a) {
		return x==a.x&&y==a.y&&r==a.y;
	}
	
}

public class p0602 {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Circle a= new Circle(2, 3, 5);
		Circle b= new Circle(2, 3, 30);
		System.out.println("원 a : "+a);
		System.out.println("원 b : "+b);
		if(a.equals(b)) {
			System.out.println("같은 원");
		}
		else {
			System.out.println("다른 원");
		}
	}

}

---

[3번]

package main;
import etc.Calc;
public class p0603 {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Calc c=new Calc(10,20);
		System.out.println(c.sum());
	}

}

package etc;

public class Calc{
	private int x,y;
	public Calc(int x,int y) {
		this.x=x;
		this.y=y;
	}
	public int sum() {
		return x+y;
	}
}

---

[4번]

package app;
import derived.Circle;
import base.Shape;
public class p0604 {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Shape shape=new Circle();
		shape.draw();
	}

}

package base;

public class Shape {
	public void draw() {System.out.println("Shape");}
}

package derived;
import base.Shape;

public class Circle extends Shape {
	public void draw() {System.out.println("Circle");}
}

---

[5번]

import java.util.Calendar;
public class p0605 {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Calendar c= Calendar.getInstance();
		int h=c.get(Calendar.HOUR_OF_DAY);
		int m=c.get(Calendar.MINUTE);
		System.out.println("현재 시간은 "+h+"시 "+m+"분 입니다.");
		if(h>=4&&h<=12) {
			System.out.println("Good Morning");
		}
		else if(h<=18){
			System.out.println("Good Evening");
		}
		else {
			System.out.println("Good Night");
		}
		
	}

}

---

[6번]

import java.util.Calendar;
import java.util.Scanner;

class game{
	String name;
	int sec;
	public game(String name) {
		this.name=name;
	}
	public void go() {
		System.out.print(name+" 시작 <Enter>키 >>");
		Scanner sc=new Scanner(System.in);
		sc.nextLine();
		Calendar c= Calendar.getInstance();
		int r1=c.get(Calendar.SECOND);
		System.out.println("\t현재 초 시간 = "+r1);
		System.out.print("10초 예상 후 <Enter>키 >>");
		sc.nextLine();
		c=Calendar.getInstance();
		int r2=c.get(Calendar.SECOND);
		System.out.println("\t현재 초 시간 = "+r2);
		sec=r2<r1?r2+60-r1:r2-r1;
	}
	public void print() {
		System.out.print(name+"의 결과 "+sec+",");
	}
}

public class p0606 {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner sc=new Scanner(System.in);
		System.out.println("10초에 가까운 사람이 이기는 게임입니다.");
		game a=new game("황기태");
		game b=new game("이재문");
		a.go();
		b.go();
		a.print();
		b.print();
		if(Math.abs(10-a.sec)>Math.abs(10-b.sec)) {
			System.out.println("승자는 "+b.name);
		}
		else if(Math.abs(10-a.sec)<Math.abs(10-b.sec)) {
			System.out.println("승자는 "+a.name);
		}
		else {
			System.out.println("비겼습니다.");
		}
	}

}

---

[7번]

import java.util.Scanner;

public class p0607 {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner sc=new Scanner(System.in);
		while(true) {
			String st=sc.nextLine();
			if(st.equals("그만")) {
				break;
			}
			String arr[]=st.split(" ");
			System.out.println("어절 개수는 "+arr.length);
		}
		System.out.println("종료합니다....");
	}

}

---

[8번]

import java.util.Scanner;

public class p0608 {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner sc=new Scanner(System.in);
		System.out.println("문자열을 입력하세요. 빈칸이 있어도되고 영어 한글 모두 됩니다.");
		String str=sc.nextLine();
		int len=str.length();
		for(int i=0;i<len;i++) {
			System.out.print(str.substring(i+1,len));
			System.out.print(str.substring(0,i+1));
			System.out.println();
		}
	}

}

---

[9번]

import java.util.Random;
import java.util.Scanner;

class rsp{
	String n;
	String name;
	public rsp(String name) {
		this.name=name;
	}
	public void Set(int op) {
		if(op==1) {
			n="가위";
		}
		else if(op==2) {
			n="바위";
		}
		else {
			n="보";
		}
	}
	public void compare(rsp b) {
		if(n.equals("가위")) {
			if(b.n.equals("가위")) {
				System.out.println("비겼습니다.");
			}
			else if(b.n.equals("바위")) {
				System.out.println(b.name+"가 이겼습니다.");
			}
			else {
				System.out.println(name+"가 이겼습니다.");
			}
		}
		else if(n.equals("바위")) {
			if(b.n.equals("가위")) {
				System.out.println(name+"가 이겼습니다.");
			}
			else if(b.n.equals("바위")) {
				System.out.println("비겼습니다.");
			}
			else {
				System.out.println(b.name+"가 이겼습니다.");
			}
		}
		else {
			if(b.n.equals("가위")) {
				System.out.println(b.name+"가 이겼습니다.");
			}
			else if(b.n.equals("바위")) {
				System.out.println(name+"가 이겼습니다.");
			}
			else {
				System.out.println("비겼습니다.");
			}
		}
	}
	public String toString() {
		return name+"("+n+")";
	}
}

public class p0609 {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner sc=new Scanner(System.in);
		rsp cs=new rsp("철수");
		rsp com=new rsp("컴퓨터");
		Random r=new Random();
		r.setSeed(System.currentTimeMillis());
		while(true) {
			System.out.print("철수[가위(1), 바위(2), 보(3), 끝내가(4)]>>");
			int op=sc.nextInt();
			if(op==4) {
				break;
			}
			cs.Set(op);
			com.Set(r.nextInt(3)+1);
			System.out.println(cs+" : "+com);
			cs.compare(com);
		}
	}

}

---

[10번]

import java.util.Random;
import java.util.Scanner;

class Person{
	String name;
	int r1,r2,r3;
	Scanner sc;
	public Person(String name) {
		this.name=name;
		sc=new Scanner(System.in);
	}
	public boolean run() {
		System.out.print("["+name+"]:<Enter>");
		String enter=sc.nextLine();
		Random r=new Random();
		r.setSeed(System.currentTimeMillis());
		r1=r.nextInt(3)+1;
		r2=r.nextInt(3)+1;
		r3=r.nextInt(3)+1;

		System.out.print("\t"+r1+"\t"+r2+"\t"+r3+"\t");
		if(r1==r2&&r2==r3) {
			System.out.println(name+"님이 이겼습니다!");
			return true;
		}
		else {
			System.out.println("아쉽군요!");
			return false;
		}
	}
}

public class p0610 {
	public static void main(String[] args) {
		Scanner sc=new Scanner(System.in);
		System.out.print("1번째 선수 이름>>");
		String n=sc.next();
		Person a=new Person(n);
		System.out.print("2번째 선수 이름>>");
		n=sc.next();
		Person b=new Person(n);
		while(true) {
			if(a.run()) break;
			if(b.run()) break;
			
		}
	}
}

---

[11번]

import java.util.Scanner;

public class p0611 {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner sc=new Scanner(System.in);
		System.out.print(">>");
		String st=sc.nextLine();
		StringBuffer sb=new StringBuffer(st);
		while(true) {
			System.out.print("명령: ");
			String op=sc.next();
			if(op.equals("그만")) {
				break;
			}
			String str[]=op.split("!");
			int index=sb.indexOf(str[0]);
			if(index==-1) {
				System.out.println("찾을 수 없습니다!");
			}
			else if(str[0].equals("")) {
				System.out.println("잘못된 명령입니다!");
			}
			else {
				sb.replace(index, index+str[0].length(), str[1]);
				System.out.println(sb);
			}
		}
		System.out.println("종료합니다");
	}

}

---

[12번]

import java.util.Random;
import java.util.Scanner;

class Person{
	String name;
	int r1,r2,r3;
	Scanner sc;
	public Person(String name) {
		this.name=name;
		sc=new Scanner(System.in);
	}
	public boolean run() {
		System.out.print("["+name+"]:<Enter>");
		String enter=sc.nextLine();
		Random r=new Random();
		r.setSeed(System.currentTimeMillis());
		r1=r.nextInt(3)+1;
		r2=r.nextInt(3)+1;
		r3=r.nextInt(3)+1;

		System.out.print("\t"+r1+"\t"+r2+"\t"+r3+"\t");
		if(r1==r2&&r2==r3) {
			System.out.println(name+"님이 이겼습니다!");
			return true;
		}
		else {
			System.out.println("아쉽군요!");
			return false;
		}
	}
}

public class p0612 {
	public static void main(String[] args) {
		Scanner sc=new Scanner(System.in);
		System.out.print("겜블링 게임에 참여할 선수 숫자>>");
		int n=sc.nextInt();
		Person arr[]=new Person[n];
		for(int i=0;i<n;i++) {
			System.out.print((i+1)+"번째 선수 이름>>");
			String name=sc.next();
			arr[i]=new Person(name);
		}
		boolean flag=true;;
		while(flag) {
			for(int i=0;i<n;i++) {
				if(arr[i].run()) {
					flag=false;
					break;
				}
			}
		}
	}
}