def pos_neg(a: int, b: int, negative: bool) -> bool:
    """Differences in signed digits.

    Return True if:
        - negative is True and both a,b < 0.
        - negative is False and
        ((a > 0 and b < 0) or (a < 0 and b > 0).
    Return False otherwise.
    """
    if negative:
        return (a < 0 and b < 0)
    return (a > 0 and b < 0) or (a < 0 and b > 0)