目标第一天学到OO部分

import math
def quadratic(a,b,c):
    delta=b*b-4*a*c
    if delta>0:
        return ((-b+math.sqrt(delta))/2/a,(-b-math.sqrt(delta))/2/a)

    elif delta==0:
        return -b/2/a

    else:
        return

print(quadratic(2,3,1))