擅长:python、mysql、java
<p>或使用<a href="http://docs.python.org/library/collections.html?highlight=defaultdict#collections.defaultdict" rel="nofollow">collections</a>模块:</p>
<pre><code>d = {'a_1_alpha':4, 'a_1_beta' :1, 'a_2_alpha' :2, 'a_2_beta': 3, 'b_1_alpha':2}
from collections import defaultdict
new_d = defaultdict(int)
for k,v in ((tuple(k.split('_')[1:]),v) for k,v in d.iteritems()):
new_d[k] += v
</code></pre>