import random
import string

def get_valid_word(words):
    """
    Returns a valid word from the provided list of words.
    Ensures the word has no spaces or hyphens and converts it to uppercase.
    """
    word = random.choice(words)
    while '-' in word or ' ' in word:
        word = random.choice(words)
    return word.upper()

def hangman():
    """
    The main function for the Hangman game.
    """
    words = ["python", "javascript", "computer", "programming", "algorithm", 
             "hangman", "challenge", "development", "random", "function"]
    word = get_valid_word(words)
    word_letters = set(word)  # Letters in the word to be guessed
    alphabet = set(string.ascii_uppercase)  # Set of uppercase English letters
    used_letters = set()  # Set of letters guessed by the user

    lives = 6

    # Main game loop
    while len(word_letters) > 0 and lives > 0:
        print(f"\nYou have {lives} lives left and you have used these letters: ", ' '.join(sorted(used_letters)))

        # Display the current state of the word
        word_list = [letter if letter in used_letters else '-' for letter in word]
        print("Current word: ", ' '.join(word_list))

        # Get user input
        user_letter = input("Guess a letter: ").upper()
        if len(user_letter) != 1 or user_letter not in alphabet:
            print("Invalid input. Please enter a single alphabet character.")
            continue

        if user_letter in used_letters:
            print("You have already used that character. Please try again.")
            continue

        # Process valid guess
        used_letters.add(user_letter)
        if user_letter in word_letters:
            word_letters.remove(user_letter)
            print("Good guess!")
        else:
            lives -= 1
            print("Letter is not in the word.")

    # End of the game
    if lives == 0:
        print(f"\nYou died. The word was {word}.")
    else:
        print(f"\nCongratulations! You guessed the word {word}!")

if __name__ == "__main__":
    hangman()