---

class NegativeValueError(Exception):
    pass


def calculate_tips(summ, percent):
    try:
        summ = float(summ)
        percent = float(percent)

        if summ < 0 or percent < 0:
            raise NegativeValueError("Одно из чисел отрицательное")

        if percent == 0:
            raise ZeroDivisionError("Процент равен нулю")

        tip = summ * percent / 100
        return tip

    except ValueError:
        print("Переданы нечисловые значения")

    except ZeroDivisionError as e:
        print(e)

    except NegativeValueError as e:
        print(e)

    finally:
        print("Расчет")