[JAVA] 명품 자바 프로그래밍 7장 실습문제

1번

import java.util.Scanner;
import java.util.Vector;

public class main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        Vector<Integer> ve = new Vector<Integer>();
        System.out.print("정수(-1이 입력 될 때 까지)>> ");
        int max = 0;
        while(true){
            int n = sc.nextInt();
            if(n == -1) break;
            ve.add(n);
            if(max < n){
                max = n;
            }
        }
        System.out.print("가장 큰 수는 " + max);
    }
}

1번

 

2번

import java.util.Scanner;
import java.util.ArrayList;

public class main {
    public static void main(String[] args) {
        ArrayList<String> arr = new ArrayList<String>();
        Scanner sc = new Scanner(System.in);
        System.out.print("6개의 학점을 빈 칸으로 분리 입력(A/B/C/D/F)>>");
        int sum = 0;
        for(int i = 0; i < 6; i++){
            String b = sc.next();
            arr.add(b);
            char a = b.charAt(0);
            if(a == 'A'){
                sum += 4;
            }
            else if(a == 'B'){
                sum += 3;
            }
            else if (a == 'C') {
                sum += 2;
            }
            else if(a=='D'){
                sum += 1;
            }
        }
        System.out.print((double)sum / (double)arr.size());
    }
}

2번

 

3번

import java.util.Scanner;
import java.util.HashMap;

public class main {
    public static void main(String[] args) {
        HashMap<String, Integer> nations = new HashMap<>();
        Scanner sc = new Scanner(System.in);
        System.out.println("나라 이름과 인구를 입력하세요.(예 : Korea 5000)");
        while(true){
            System.out.print("나라 이름, 인구 >>");
            String temp1 = sc.next();
            if(temp1.equals("그만")) break;
            int temp2 = sc.nextInt();
            nations.put(temp1, temp2);
        }
        while(true){
            System.out.print("인구 검색>>");
            String temp = sc.next();
            if(temp.equals("그만")) break;


            if(nations.get(temp) == null){
                System.out.println(temp + " 나라는 없습니다.");
            }
            else {
                System.out.println(temp + "의 인구는 " + nations.get(temp));
            }
        }
    }
}

3번

 

4번

import java.util.Scanner;
import java.util.Vector;

public class main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        Vector<Integer> ve = new Vector<>();
        while(true){
            System.out.print("강수량 입력 (0 입력시 종료) >> ");
            int temp = sc.nextInt();
            if(temp == 0) break;
            ve.add(temp);
            int sum = 0;
            for(int i = 0; i < ve.size(); i++){
                System.out.print(ve.get(i) + " ");
                sum += ve.get(i);
            }
            System.out.println("\n현재 평균 " + sum / ve.size());
        }
    }
}

4번

 

5번

import java.util.ArrayList;
import java.util.Scanner;
import java.util.StringTokenizer;

class Student{
    private String name, major, id, grade;
    public Student() {}
    public Student(String name, String major, String id, String grade) {this.name = name; this.major = major; this.id = id; this.grade = grade;}
    public String getName() {return name;}
    public String getMajor() {return major;}
    public String getId() {return id;}
    public String getGrade() {return grade;}
    public void find_student(String name) {
        if(name.equals(this.name)) {
            System.out.println(this.name+", "+this.major+", "+this.grade+", "+this.grade);
        }
    }
}

public class main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        System.out.println("학생 이름, 학과, 학점 평균을 입력하세요.");
        ArrayList<Student> arr = new ArrayList<>();
        for(int i = 0; i < 4; i++){
            System.out.print(">> ");
            String s = sc.nextLine();
            StringTokenizer st = new StringTokenizer(s, ",");
            String name = st.nextToken();
            String major = st.nextToken();
            String id = st.nextToken();
            String grade = st.nextToken();
            arr.add(new Student(name, major, id, grade));
        }
        System.out.println("----------------------");
        for(int i = 0; i < 4; i++){
            System.out.println("이름: " + arr.get(i).getName());
            System.out.println("학과: " + arr.get(i).getMajor());
            System.out.println("학번: " + arr.get(i).getId());
            System.out.println("학점평균: " + arr.get(i).getGrade());
            System.out.println("----------------------");
        }
        while (true){
            System.out.println("학생 이름 >>");
            String name = sc.nextLine();
            if(name.equals("그만")) break;
            for(int i = 0; i < arr.size(); i++){
                Student s = arr.get(i);
                s.find_student(name);
            }
        }
    }
}

5번

 

6번

import java.util.HashMap;
import java.util.Iterator;
import java.util.Scanner;
import java.util.Set;
import java.util.StringTokenizer;

class Location{
    private int first, second;
    public Location(int first, int second) {this.first = first; this.second = second;}
    public void find_location(String city){System.out.println(city + " " + first + " " + second); }
}

public class main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        System.out.println("학생 이름, 학과, 학점 평균을 입력하세요.");
        HashMap<String, Location> hm = new HashMap<>();

        for(int i = 0; i < 4; i++){
            System.out.print(">>");
            String str = sc.nextLine();
            StringTokenizer st = new StringTokenizer(str, ",");
            String name = st.nextToken();
            int first = Integer.parseInt(st.nextToken().trim());
            int second = Integer.parseInt(st.nextToken().trim());
            hm.put(name, new Location(first, second));
        }
        System.out.println("----------------------------------");
        Set<String> key = hm.keySet();
        Iterator <String> it = key.iterator();
        while(it.hasNext()){
            String temp = it.next();
            Location s = hm.get(temp);
            s.find_location(temp);
        }
        System.out.println("----------------------------------");
        while(true) {
            System.out.print("도시 이름 >> ");
            String city = sc.next();
            if(city.equals("그만"))
                break;
            Location s = hm.get(city);
            if( s == null)
                System.out.println(city+"는 없습니다.");
            else
                s.find_location(city);
        }
        sc.close();
    }
}

6번

 

7번

import java.util.HashMap;
import java.util.Iterator;
import java.util.Scanner;
import java.util.Set;


public class main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        System.out.println("미래장학금관리시스템입니다.");
        HashMap<String, Double> hm = new HashMap<>();
        for(int i = 0; i < 5; i++){
            System.out.print("이름과 학점 >> ");
            String name = sc.next();
            double score = sc.nextDouble();
            hm.put(name, score);
        }
        System.out.print("장학금 선발 학점 기준 입력>> ");
        double fixScore = sc.nextDouble();
        Set<String> key = hm.keySet();
        Iterator <String> it = key.iterator();
        while (it.hasNext()){
            String name = it.next();
            if(fixScore < hm.get(name)){
                System.out.print(name + " ");
            }
        }
    }
}

7번

 

8번

import java.util.HashMap;
import java.util.Iterator;
import java.util.Scanner;
import java.util.Set;


public class main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        System.out.println("** 포인트 관리 프로그램입니다. **");
        HashMap<String, Integer> hm = new HashMap<>();
        while (true) {
            System.out.print("이름과 포인트 입력 >> ");
            String name = sc.next();
            if (name.equals("그만")) break;
            int score = sc.nextInt();
            if (hm.get(name) == null) {
                hm.put(name, score);
            } else {
                hm.put(name, score + hm.get(name));
            }
            Set<String> key = hm.keySet();
            Iterator <String> it = key.iterator();
            while (it.hasNext()){
                String str = it.next();
                    System.out.print("(" + str + "," + hm.get(str) + ")");
            }
            System.out.println();
        }
    }
}

8번

 

9번

import java.util.*;

interface IStack<T> {
    T pop();
    boolean push(T ob);
}

class MyStack<T> implements IStack<T>{
    private ArrayList<T> al;
    public MyStack() {al = new ArrayList<>();}
    public T pop(){
        if(al.size() != 0){
            return al.remove(0);
        }
        return null;
    }
    public boolean push(T ob){
        al.add(0, ob);
        return true;
    }
}

public class main {
    public static void main(String[] args) {
        IStack<Integer> stack = new MyStack<Integer>();
        for (int i=0; i<10; i++) stack.push(i);
        while(true) {
            Integer  n = stack.pop();
            if(n == null) break;
            System.out.print(n+" ");
        }
    }
}

9번

 

10번

import java.util.*;

abstract class Shape {
    private Shape next;
    public Shape() { next = null; }
    public void setNext(Shape obj) { next = obj; } //링크 연결
    public Shape getNext() { return next; }
    public abstract void draw();
}
class Line extends Shape {
    public void draw() {
        System.out.println("Line");
    }
}
class Rect extends Shape {
    public void draw() {
        System.out.println("Rect");
    }
}
class Circle extends Shape {
    public void draw() {
        System.out.println("Circle");
    }
}

public class main {
    public static void main(String[] args) {
        System.out.println("그래픽 에디터 beauty를 실행합니다.");
        Vector<Shape> ve = new Vector<>();
        Scanner sc = new Scanner(System.in);
        while(true){
            System.out.print("삽입(1), 삭제(2), 모두 보기(3), 종료(4)>>");
            int input = sc.nextInt();
            if(input == 1){
                System.out.print("Line(1), Rect(2), Circle(3)>>");
                int input1 = sc.nextInt();
                if(input1 == 1){
                    ve.add(new Line());
                }
                else if(input1 == 2){
                    ve.add(new Rect());
                }
                else if(input1 == 3){
                    ve.add(new Circle());
                }
                else {

                }
            }
            else if(input == 2){
                System.out.print("삭제할 도형의 위치 >>");
                int input1 = sc.nextInt();
                if(ve.size() > input1){
                    if(ve.get(input1) == null){
                        System.out.println("삭제할 수 없습니다.");
                    }
                    else{
                        ve.remove(input1);
                    }
                }
                else{
                    System.out.println("삭제할 수 없습니다.");
                }

            }
            else if(input == 3){
                for(int i = 0; i < ve.size(); i++){
                    ve.get(i).draw();
                }
            }
            else{
                break;
            }
        }
    }
}

10번

 

11번

import java.util.*;

class Nation {
    private String country;
    private String capital;
    public Nation(String country, String capital) {
        this.country = country;
        this.capital = capital;
    }
    public String getCountry() {
        return country;
    }
    public String getCapital() {
        return capital;
    }
}

class CaptialQuiz{
    private Vector<Nation> na;
    private Scanner sc;
    public CaptialQuiz() {
        na = new Vector<>();
        sc = new Scanner(System.in);
        na.add(new Nation("멕시코", "멕시코시티"));
        na.add(new Nation("스페인", "리스본"));
        na.add(new Nation("프랑스", "파리"));
        na.add(new Nation("영국", "런던"));
        na.add(new Nation("그리스", "아테네"));
        na.add(new Nation("독일", "베를린"));
        na.add(new Nation("일본", "동경"));
        na.add(new Nation("중국", "베이징"));
        na.add(new Nation("러시아", "모스크바"));
    }
    public void run(){
        while(true){
            System.out.print("입력:1, 퀴즈:2, 종료:3>> ");
            int input = sc.nextInt();
            if(input == 1){
                insert();
            }
            else if(input == 2){
                play();
            }
            else if(input == 3){
                break;
            }
            else {
                System.out.println("잘못 된 입력입니다.");
            }
        }
    }
    public void insert(){
        System.out.println("현재 " + na.size() + "개 나라와 수도가 입력되어 있습니다.");
        while(true){
            System.out.print("나라와 수도 입력" + (int)(na.size() + 1) + ">>");
            String first = sc.next();
            if(first.equals("그만")) break;
            String second = sc.next();
            boolean isIn = false;
            for(int i = 0; i < na.size(); i++){
                if(na.get(i).getCountry().equals(first)){
                    isIn = true;
                    break;
                }
            }
            if(isIn){
                System.out.println(first + "는 이미 있습니다!");
                continue;
            }
            na.add(new Nation(first, second));
        }
    }
    public void play(){
        while (true){
            int index = (int)(Math.random() * na.size());
            System.out.print(na.get(index).getCountry() + "의 수도는?");
            String inputs = sc.next();
            if(inputs.equals("그만")) break;
            if(inputs.equals(na.get(index).getCapital())){
                System.out.println("정답!");
            }
            else{
                System.out.println("아닙니다!!");
            }
        }
    }
}

public class main {
    public static void main(String[] args){
        CaptialQuiz cq = new CaptialQuiz();
        cq.run();
    }
}

11번

 

12번

import java.util.*;

class Word {
    private String eng;
    private String kor;
    public Word(String eng, String kor) {
        this.eng = eng;
        this.kor = kor;
    }
    public String getEng() {
        return eng;
    }
    public String getKor() {
        return kor;
    }
}

class EngQuiz{
    private Vector<Word> ve;
    private Scanner sc;
    public EngQuiz() {
        ve = new Vector<>();
        sc = new Scanner(System.in);
        ve.add(new Word("love", "사랑"));
        ve.add(new Word("animal", "동물"));
        ve.add(new Word("emotion", "감정"));
        ve.add(new Word("human", "인간"));
        ve.add(new Word("stock", "주식"));
        ve.add(new Word("trade", "거래"));
        ve.add(new Word("society", "사회"));
        ve.add(new Word("baby", "아기"));
        ve.add(new Word("honey", "꿀"));
        ve.add(new Word("dall", "인형"));
        ve.add(new Word("bear", "곰"));
        ve.add(new Word("picture", "사진"));
        ve.add(new Word("painting", "그림"));
        ve.add(new Word("fault", "오류"));
        ve.add(new Word("example", "보기"));
        ve.add(new Word("eye", "눈"));
        ve.add(new Word("statue", "조각상"));
    }
    void run(){
        System.out.println("**** 영어 단어 테스트 프로그램 \"명품 영어\"입니다. ****");
        while (true){
            try {
                System.out.print("단어 테스트:1, 단어 삽입:2, 종료:3>> ");
                int input = sc.nextInt();
                if(input == 1){
                    play();
                }
                else if(input == 2){
                    insert();
                }
                else if(input == 3){
                    break;
                }
                else{
                    System.out.println("잘못된 입력 다시 입력해주세요.");
                }
            }
            catch (Exception ex) {
                System.out.println("잘못된 입력");
                String buffer = sc.nextLine();
                continue;
            }
        }
    }

    void play(){
        System.out.println("현재 " + ve.size() + "개의 단어가 들어 있습니다. -1을 입력하면 종료합니다.");
        while(true){
            int[] arr = {-1, -1, -1, -1};
            int arrRandInt = (int)(Math.random() * 4);
            int randInt = (int)(Math.random()*ve.size());
            arr[arrRandInt] = randInt;
            System.out.println(ve.get(randInt).getEng() + "?");
            for(int i = 0; i < arr.length; i++){
                if(arr[i] != -1 || arr[i] == arrRandInt){
                    continue;
                }
                else{
                    int tempRand = (int)(Math.random() * ve.size());
                    for(int j = 0; j < i; j++){
                        if(tempRand == arr[j]){
                            j = 0;
                            tempRand = (int)(Math.random() * ve.size());
                        }
                    }
                    arr[i] = tempRand;
                }
            }
            for(int j = 0; j < arr.length; j++){
                System.out.print("(" + (int)(j+1) + ")" + ve.get(arr[j]).getKor() + " ");
            }
            System.out.print(":>");
            int n = sc.nextInt();
            if(n == (int)(arrRandInt + 1)){
                System.out.println("Exellent!");
            }
            else if(n == -1){
                break;
            }
            else {
                System.out.println("No!");
            }
        }
    }

    void insert(){
        System.out.println("영어 단어에 그만을 입력하면 입력을 종료합니다.");
        while (true){
            System.out.print("영어 한글 입력 >>");
            String eng = sc.next();
            if(eng.equals("그만")) break;
            String kor = sc.next();
            ve.add(new Word(eng, kor));
        }
    }

}

public class main {
    public static void main(String[] args){
        EngQuiz eq = new EngQuiz();
        eq.run();
    }
}

12번