生成器和迭代器练习案例

1、实现enumerate函数

def enumerate_generator(iterable):
    for i in range(len(iterable)):
        yield i,iterable[i]

gen_e = enumerate_generator(['a','b','c','d'])
for e in gen_e:
    print(e)

运行结果：

(0, 'a')
(1, 'b')
(2, 'c')
(3, 'd')

2、实现zip函数

def zip_generator(*args):
    len_list = []
    for i in args:
        len_list.append(len(i))
    for n in range(min(len_list)):
        t = ()
        for i in args:
            t += (i[n],)
        yield t

gen_z = zip_generator([1,2,3,4],('a','b','c','d','e'),['A','B','C'])
for z in gen_z:
    print(z)

运行结果：

(1, 'a', 'A')
(2, 'b', 'B')
(3, 'c', 'C')

3、不使用for循环，遍历列表[1,2,3,4,5,6,7,8,9,10]

a_list = [1,2,3,4,5,6,7,8,9,10]
iter_list = a_list.__iter__() #变成迭代器
while True:
    try:
        res = next(iter_list)
    except:
        break
    else:
        print(res)

运行结果：

1
2
3
4
5
6
7
8
9
10