if a == 0:
    print('此方程的解为：x = %.1f' %(-c/b))
else:
    delta = b**2 - 4* a * c
    if delta < 0:
        print('此方程没有实数根~')

elif delta == 0:

x =(-b + math.sqrt(delta)) / (2 * a)

print('此方程具有唯一解：x=')

return x

    else:
        x1 = (-b + math.sqrt(delta)) / (2 * a)
        x2 = (-b - math.sqrt(delta)) / (2 * a)
        print('此方程的解为：(x1,x2) =')
        return x1,x2 

print(quadratic(1,2,3)) print(quadratic(0,2,3))