// Java Voting App (console-based)
        import java.util.*;

class User {
    private String username;
    private String password;
    private boolean hasVoted;

    private static Map userdb = new HashMap<>();

    public User(String username, String password) {
        this.username = username;
        this.password = password;
        this.hasVoted = false;
    }

    public static boolean addUser(String username, String password) {
        if (userdb.containsKey(username)) {
            System.out.println("User already exists.");
            return false;
        }
        userdb.put(username, new User(username, password));
        return true;
    }

    public static User authenticate(String username, String password) {
        User user = userdb.get(username);
        if (user != null && user.password.equals(password)) {
            return user;
        }
        return null;
    }

    public boolean hasVoted() {
        return hasVoted;
    }

    public void setHasVoted(boolean hasVoted) {
        this.hasVoted = hasVoted;
    }
}

class VotingSystem {
    private Map parties;

    public VotingSystem() {
        parties = new HashMap<>();
        parties.put("a", 0);
        parties.put("b", 0);
        parties.put("c", 0);
    }

    public void voteUser(Scanner scanner) {
        System.out.print("Enter username: ");
        String username = scanner.nextLine();
        System.out.print("Enter password: ");
        String password = scanner.nextLine();

        User user = User.authenticate(username, password);
        if (user != null) {
            if (user.hasVoted()) {
                System.out.println("You have already voted.");
                return;
            }

            System.out.println("Available parties: a, b, c");
            System.out.print("Enter party name: ");
            String choice = scanner.nextLine().toLowerCase();

            if (parties.containsKey(choice)) {
                parties.put(choice, parties.get(choice) + 1);
                user.setHasVoted(true);
                System.out.println("Vote cast successfully.");
            } else {
                System.out.println("Invalid party.");
            }
        } else {
            System.out.println("Invalid credentials.");
        }
    }

    public void viewResults() {
        System.out.println("\nVoting Results:");
        for (Map.Entry entry : parties.entrySet()) {
            System.out.println("Party " + entry.getKey() + ": " + entry.getValue() + " vote(s)");
        }
    }
}

public class VotingSystemApp {
    public static void registerUser(Scanner scanner) {
        System.out.print("Enter username: ");
        String username = scanner.nextLine();
        System.out.print("Enter password: ");
        String password = scanner.nextLine();
        if (User.addUser(username, password)) {
            System.out.println("User registered successfully.");
        } else {
            System.out.println("Registration failed.");
        }
    }

    public static void loginUser(Scanner scanner) {
        System.out.print("Enter username: ");
        String username = scanner.nextLine();
        System.out.print("Enter password: ");
        String password = scanner.nextLine();
        User user = User.authenticate(username, password);
        if (user != null) {
            System.out.println("Login successful.");
        } else {
            System.out.println("Invalid credentials.");
        }
    }

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        VotingSystem votingSystem = new VotingSystem();

        while (true) {
            System.out.println("\n1. Register");
            System.out.println("2. Login");
            System.out.println("3. Vote");
            System.out.println("4. View Results");
            System.out.println("5. Exit");
            System.out.print("Enter your choice: ");
            String choice = scanner.nextLine();

            switch (choice) {
                case "1":
                    registerUser(scanner);
                    break;
                case "2":
                    loginUser(scanner);
                    break;
                case "3":
                    votingSystem.voteUser(scanner);
                    break;
                case "4":
                    votingSystem.viewResults();
                    break;
                case "5":
                    System.out.println("Exiting program.");
                    scanner.close();
                    return;
                default:
                    System.out.println("Invalid choice. Please try again.");
            }
        }
    }
}

    

# Python Voting App (console-based)
        import getpass

class User:
    userdb = {}

    def __init__(self, username, password):
        self.username = username
        self.password = password
        self.has_voted = False

    @classmethod
    def add_user(cls, username, password):
        if username in cls.userdb:
            print("❌ User already exists!")
            return False
        cls.userdb[username] = User(username, password)
        return True

    @classmethod
    def authenticate(cls, username, password):
        user = cls.userdb.get(username)
        if user and user.password == password:
            return user
        return None

def register_user():
    username = input("Enter username: ")
    password = getpass.getpass("Enter password: ")
    if User.add_user(username, password):
        print("✅ Registered successfully.")
    else:
        print("❌ Registration failed.")

def login_user():
    username = input("Enter username: ")
    password = getpass.getpass("Enter password: ")
    user = User.authenticate(username, password)
    if user:
        print("✅ Login successful.")
        if user.has_voted:
            print("🗳️ You have already voted.")
        else:
            print("🟢 You can vote now.")
            vote = input("Who do you vote for? ")
            user.has_voted = True
            print(f"✅ Vote casted for {vote}")
    else:
        print("❌ Login failed.")

# Example usage:
while True:
    print("\n1. Register\n2. Login\n3. Exit")
    choice = input("Choose option: ")
    if choice == "1":
        register_user()
    elif choice == "2":
        login_user()
    elif choice == "3":
        break
    else:
        print("❌ Invalid choice")

    

# JavaScript Voting App (console-based)
        const readline = require('readline');

class User {
    static userdb = new Map();

    constructor(username, password) {
        this.username = username;
        this.password = password;
        this.has_voted = false;
    }

    static add_user(username, password) {
        if (User.userdb.has(username)) {
            console.log("❌ User already exists!");
            return false;
        }
        User.userdb.set(username, new User(username, password));
        return true;
    }

    static authenticate(username, password) {
        const user = User.userdb.get(username);
        if (user && user.password === password) {
            return user;
        }
        return null;
    }
}

function register_user() {
    const username = readline.question("Enter username: ");
    const password = readline.question("Enter password: ", { hideEchoBack: true });
    if (User.add_user(username, password)) {
        console.log("✅ Registered successfully.");
    } else {
        console.log("❌ Registration failed.");
    }
}

function login_user() {
    const username = readline.question("Enter username: ");
    const password = readline.question("Enter password: ", { hideEchoBack: true });
    const user = User.authenticate(username, password);
    if (user) {
        console.log("✅ Login successful.");
        if (user.has_voted) {
            console.log("🗳️ You have already voted.");
        } else {
            console.log("🟢 You can vote now.");
            const vote = readline.question("Who do you vote for? ");
            user.has_voted = true;
            console.log(✅ Vote casted for ${vote});
        }
    } else {
        console.log("❌ Login failed.");
    }
}

// Example usage:
const rl = readline.createInterface({
    input: process.stdin,
    output: process.stdout
});

function main() {
    rl.question("\n1. Register\n2. Login\n3. Exit\nChoose option: ", (choice) => {
        switch (choice) {
            case "1":
                register_user();
                break;
            case "2":
                login_user();
                break;
            case "3":
                rl.close();
                return;
            default:
                console.log("❌ Invalid choice");
        }
        main();
    });
}

main();