은행계좌시스템

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

class Account{
	String account_num;
	String depositor;
	String date;
	int balance;
}

public class BankSystem {

	public static void main(String[] args) {

		Account acc_arr[] = new Account[100];
		int acc_idx = 0;
		boolean flag = true;
		
		Scanner sc = new Scanner(System.in);
		
		while(flag) {
			System.out.println("원하는 서비스의 번호를 입력하세요. 1)계좌계설 2)현재 개설된 계좌 정보보기 3)시스템 종료");
			
			int service_num = sc.nextInt();
			switch(service_num) {
			case 1:
				System.out.println("예금주:");
				Account acc = new Account();
				acc.depositor = sc.next();
				System.out.println("예금할 금액 :");
				acc.balance = sc.nextInt();
				Calendar cal = Calendar.getInstance();
				acc.date = cal.get(Calendar.YEAR) +"-"+ (cal.get(Calendar.MONTH) + 1) + "-"+cal.get(Calendar.DATE);
				acc.account_num = "1002-" + (int)((Math.random()*99)+1) +"-"+(int)((Math.random()*9999999)+1);
				System.out.println("예금주 "+ acc.depositor + "님 앞으로 생성된 계좌번호는 " + acc.account_num +" 입니다.");
				System.out.println();
				acc_arr[acc_idx++] = acc;
				
				break;
			case 2:
				System.out.println("-----------개설된 계좌 정보-----------");
				for(int i = 0; i<acc_idx; i++)
					System.out.println("계좌번호:" +acc_arr[i].account_num+", 예금주 :" + acc_arr[i].depositor+", 잔액 :" + acc_arr[i].balance);
				System.out.println("----------------------------------");
				System.out.println();
				break;
			case 3:
				flag = false;
				break;
			default:
				break;
				}
			}
		}
	}