擅长:python、mysql、java
<p>这样的解决方案很酷</p>
<p><a href="https://twitter.com/raymondh/status/343823801278140417" rel="nofollow">https://twitter.com/raymondh/status/343823801278140417</a></p>
<pre><code>>>> from collections import defaultdict
>>> infinite_defaultdict = lambda: defaultdict(infinite_defaultdict)
>>> d = infinite_defaultdict()
>>> d['x']['y']['z'] = 10
>>> if d['x']['y']['z']: print d['x']['y']['z'] #better reflects that misses are common
</code></pre>