def get_quartile_position(number: float, is_even: float = False) -> [int, tuple]:
    if is_even:
        number = int(number)
        return number, number + 1
    return round(number)


def get_positions(total_population: int) -> tuple[any, any, any]:
    even_population = total_population % 2 == 0
    has_even_quartiles = (total_population // 2) % 2 == 0
    total_population += 1
    q1_position = total_population / 4
    q1_position = get_quartile_position(q1_position, has_even_quartiles)
    q2_position = total_population / 2
    q2_position = get_quartile_position(q2_position, even_population)
    q3_position = (3 * total_population) / 4
    q3_position = get_quartile_position(q3_position, has_even_quartiles)

    return q1_position, q2_position, q3_position


def get_quartiles_values(group: dict, pos: [int, tuple]) -> int:
    if type(pos) is tuple:
        return round((group[pos[0]] + group[pos[1]]) / 2)

    return group[pos]


def quartiles(arr) -> list[int]:
    arr.sort()
    n = len(arr)
    arr = dict(enumerate(arr, start=1))
    return list(map(lambda pos: get_quartiles_values(arr, pos), get_positions(n)))