列表列表中的项目索引(Python)

Question

我试图在下面的列表列表中找到一个字母的索引:

例如:

>>> alphabet = [[["A","B","C"],["D","E","F"],["G","H","I"]],[["J","K","L"],["M","N","O"],["P","Q","R"]],[["S","T","U"],["V","W","X"],["Y","Z","_"]]]
>>> find("H",alphabet)
(0,2,1)

最恐怖的做法是什么？

Answer 1

如果你真的想要一个处理任何深度的解决方案,这就是你要寻找的东西(作为一个简单的递归函数):

def find_recursive(needle, haystack):
    for index, item in enumerate(haystack):
        if not isinstance(item, str):
            try:
                path = find_recursive(needle, item)
                if path is not None:
                    return (index, ) + path
            except TypeError:
                pass
        if needle == item:
            return index,
    return None

编辑:记住,在2.x中,你想要basestring允许unicode字符串 - 这个解决方案对于3.x用户来说很好.