import cmath


class Complex(complex):
    def __repr__(self):
        rp = '%7.5f' % self.real if not self.pureImag() else ''
        ip = '%7.5fj' % self.imag if not self.pureReal() else ''
        conj = '' if (
            self.pureImag() or self.pureReal() or self.imag < 0.0
        ) else '+'
        return '0.0' if (
            self.pureImag() and self.pureReal()
        ) else rp + conj + ip

    def pureImag(self):
        return abs(self.real) < 0.000005

    def pureReal(self):
        return abs(self.imag) < 0.000005


def croots(n):
    if n <= 0:
        return None
    return (Complex(cmath.rect(1, 2 * k * cmath.pi / n)) for k in range(n))
    # in pre-Python 2.6:
    #   return (Complex(cmath.exp(2j*k*cmath.pi/n)) for k in range(n))


for nr in range(2, 11):
    print(nr, list(croots(nr)))