擅长:python、mysql、java
<p>您还可以使用collections counter(这是计数事物时的自然go-to函数,它返回一个字典):</p>
<pre><code>from collections import Counter
vowels = list('aeiou')
wordlist = ['big', 'cats', 'like', 'really']
lettersum = Counter(''.join(wordlist))
print('\n'.join(['"{}" occurs {} time(s).'.format(i,lettersum.get(i,0)) for i in vowels]))
</code></pre>
<p>退货:</p>
^{pr2}$
<p>信笺:</p>
<pre><code>Counter({'l': 3, 'a': 2, 'e': 2, 'i': 2, 'c': 1, 'b': 1,
'g': 1, 'k': 1, 's': 1, 'r': 1, 't': 1, 'y': 1})
</code></pre>