// Main program
// Java auto includes the other UserData class
import java.io.*;
import java.util.*;

public class Main {
    public static void main(String[] args) {
        Vector<UserPass> Storage = new Vector<UserPass>();
        Scanner input = new Scanner(System.in);
        Character selChar;
        UserPass temp = new UserPass();
        do{
            temp = new UserPass();
            System.out.println("Enter Command:");
            System.out.println("L - Login");
            System.out.println("N - New User");
            System.out.println("S - Show All User Data");
            System.out.println("E - Exit");
            System.out.print("Selection:");
            String sel= input.nextLine();
            selChar= sel.charAt(0);
            switch(selChar)
            {
                case 'l': case 'L':
                {
                    System.out.println("Enter Name:");
                    temp.username = input.nextLine();
                    System.out.println("Enter Password:");
                    temp.password = input.nextLine();
                    Boolean verified=false;
                    for(Integer i=0; i<Storage.size(); i++)
                    {
                        if((temp.username == Storage.elementAt(i).username)
                            && (temp.password==Storage.elementAt(i).password))
                        {       verified=true;
                        }else
                        {}
                    }
                    if(verified)
                        System.out.println("Correct!");
                    else
                        System.out.println("Invalid username/password!");
                }break;
                case 'n': case 'N':
                {
                    System.out.println("Enter Name:");
                    temp.username = input.nextLine();
                    System.out.println("Enter Password:");
                    temp.password = input.nextLine();
                    Storage.add(temp);
                    }break;
                case 's': case 'S':
                    System.out.println("**Printing User Data**");
                    for(Integer i=0; i<Storage.size(); i++)
                    {
                        System.out.println(Storage.elementAt(i).username + "," + Storage.elementAt(i).password);
                    }
                    System.out.println("**End of Usernames/Passwords**");
                default: break;
            }
            } while(!(selChar=='E' || selChar=='e'));
        }
   }


// Storage for username and passwords
// This goes in a file called UserPass.java
import java.io.*;

public class UserPass
{
        String username;
        String password;
}