def noncov_btwn_sta(place1: float, place2: float,
                    cov1: float, cov2: float) -> float:
    """
    Calculate noncoverage between place1 and place2
    :param place1:
    :param place2:
    :param cov1:
    :param cov2:
    :return: Noncoverage between two placed station
    """
    dist = abs(place2 - place1)
    cov = cov1 + cov2
    return max([dist - cov, 0])