Python练习笔记——字符串反转

请输入一段字符串，不利用反转函数，编写一段代码，将其反转。

 

def list_reverse(a):
    list_long = len(a)
    list_long_half = list_long // 2
    # 1 2 3    1 2 3 4   1 2 3 4 5
    for i in range(list_long_half):
        j = a[i]       #a[0]
        a[i] = a[-i-1] #a[0]=a[-1]
        a[-i-1] = j    #a[-1]=a[0]
    return a


b1 = [1,2,3,4,5,6]
c1 = [1,2,3,4,5,6,7]

b2 = list_reverse(b1)
c2 = list_reverse(c1)

print(b1)
print(c1)
print(b2)
print(c2)

运行输出

[6, 5, 4, 3, 2, 1]
[7, 6, 5, 4, 3, 2, 1]
[6, 5, 4, 3, 2, 1]
[7, 6, 5, 4, 3, 2, 1]