004_006 Python 展开嵌套序列 序列的子序列进行展开

代码如下：

#encoding=utf-8print '中国'#展开嵌套序列 序列的子序列进行展开print '----递归'def list_or_tuple(x):    return isinstance(x,(list,tuple))def flatten(sequence, to_expand=list_or_tuple):    for item in sequence:        if to_expand(item):            for subitem in flatten(item,to_expand):                yield subitem        else:            yield item            lista=[[1,2,[3,4,[5,6]]],7,8,(9,10,(11,12))]for idx,item in enumerate(flatten(lista)):    print idx,item    print '----非递归 链表'def flatten2(sequence, to_expand=list_or_tuple):    iterators = [ iter(sequence) ]    while iterators:               for item in iterators[-1]:            if to_expand(item):                                iterators.append(iter(item))                break            else:                yield item        else:                        iterators.pop( )for idx,item in enumerate(flatten2(lista)):    print idx,item    

打印结果如下：

中国
----递归
0 1
1 2
2 3
3 4
4 5
5 6
6 7
7 8
8 9
9 10
10 11
11 12
----非递归 链表
0 1
1 2
2 3
3 4
4 5
5 6
6 7
7 8
8 9
9 10
10 11
11 12