擅长:python、mysql、java
<p>下面是另一种面向词典的方法:</p>
<pre><code>l = [0, 1, 1, 2, 2]
d = {}
for i in l: d[i] = i in d
[k for k in d if not d[k]] # unordered, loop over the dictionary
[k for k in l if not d[k]] # ordered, loop over the original list
</code></pre>