JavaStudy02_4_2.java

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

public class ListAssignment {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        ArrayList contact = new ArrayList();

        String name, num;
        boolean flag = true;
        int searchIdx, beforeSize, afterSize;

        while (flag) {
            System.out.println("연락처 관리 시스템(add, remove, list, search, exit");
            System.out.print("명령 입력 : ");
            String cmdStr = sc.nextLine();

            switch (cmdStr) {
                case "add":
                    beforeSize = contact.size();
                    System.out.print("이름 : ");
                    name = sc.nextLine();
                    contact.add(name);
                    System.out.print("번호 : ");
                    num = sc.nextLine();
                    contact.add(num);
                    afterSize = contact.size();
                    if (beforeSize < afterSize) System.out.println("연락처 추가");
                    else System.out.println("연락처 추가 실패");
                    break;
                case "remove":
                    beforeSize = contact.size();
                    System.out.print("삭제할 이름 : ");
                    name = sc.nextLine();
                    searchIdx = contact.indexOf(name);
                    contact.remove(searchIdx);
                    contact.remove(searchIdx + 1);
                    afterSize = contact.size();
                    if(beforeSize>afterSize) System.out.println("연락처 삭제");
                    else System.out.println("연락처 삭제 실패");
                    break;
                case "list":

                    break;
                case "search":
                    System.out.print("검색할 이름 : ");
                    name = sc.nextLine();
                    searchIdx = contact.indexOf(name);
                    System.out.println(contact.get(searchIdx) + " - " + contact.get(searchIdx + 1));
                    break;
                case "exit":
                    flag = false;
                    break;
            }
        }
    }
}