Python笔记三

用for循环表达一个字符串

a =  input()
for i in a:
    print(i)

求一元二次方程的解

def num1(a,b,c):
    delta = b**2-4*a*c
    if delta < 0:
        print("无解")
    elif delta==0:
        s = -b/(2*a)
        print("唯一根x=",s)
    else:
        e = ((-b)+(b**2-4*a*c)**1/2)/2*a
        d = ((-b)-(b**2-4*a*c)**1/2)/2*a
        return e,d