来我们直接上代码
Python 2.7.9 (default, Mar 1 2015, 12:57:24)
[GCC 4.9.2] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> x = 'momoda'
>>> dy = [x for x in 'NICE']
>>> x
'E'
>>>
再看这个
Python 3.4.2 (default, Oct 8 2014, 10:45:20)
[GCC 4.9.1] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> x = 'momoda'
>>> dy = [x for x in 'NICE']
>>> x
'momoda'
很有趣不是么?
我们都知道python遍历数组是十分方便的。
>>> b = [i for i in range(10)]
>>> b
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
>>> for i in b:
... print(i)
...
0
1
2
3
4
5
6
7
8
9
但是如何在遍历数组的同时获得当前下标?for i in range(len(b)): ?再通过下标寻址?
所幸python提供了一个极为方便的内建函数enumerate()
>>> for no, i in enumerate(b):
... print(no, i)
...
0 0
1 1
2 2
3 3
4 4
5 5
6 6
7 7
8 8
9 9
可以看到成功的输出了当前下标!
同时我们也可以从任意位置开始
>>> for no, i in enumerate(b):
... print(no, i)
...
0 0
1 1
2 2
3 3
4 4
5 5
6 6
7 7
8 8
9 9