擅长:python、mysql、java
<p><code>defaultdict</code>可能是一个很好的方法,但是你可以用普通的字典:</p>
<pre><code>>>> data = [['Acer', 481242.74], ['Beko', 966071.86], ['Cemex', 187242.16], ...]
>>> result = {}
>>> for k, v in data:
... result[k] = result.get(k, 0) + v
>>> result
{'Acer': 533395.76848, 'Beko': 966071.86, 'Cemex': 187242.16, ... }
>>> list(result.items())
[('Acer', 533395.76848), ('Beko', 966071.86), ('Cemex', 187242.16), ...]
</code></pre>