def new_dashed_word(a, b, c):
    """
    This function compose th new dashed_word after user guessed the correct characters.
    :param a: int, the index of the correct character in the_word.
    :param b: str, representing dashed_word
    :param c: str, representing the_word
    :return: str, the new dashed word.
    """
    ans = ''
    ans += b[:a]
    ans += c[a]
    ans += b[a + 1:]
    return ans