擅长:python、mysql、java
<p>您必须对其进行计数和排序,如下例所示:</p>
<pre><code>>>> from collections import defaultdict
>>> l = [1,5,1,1,6,3,3,4,5,5,5,2,5]
>>> d = defaultdict(int)
>>> for e in l:
... d[e] += 1
...
>>> print sorted(d,key=lambda e:d[e])
[2, 4, 6, 3, 1, 5]
</code></pre>