擅长:python、mysql、java
<p>这看起来像是<a href="https://docs.python.org/3/library/itertools.html#itertools.groupby" rel="nofollow">itertools.groupby</a>的任务。在</p>
<pre><code>from itertools import groupby
data = 'aaaabbсaa'
compressed = ''.join('{}{}'.format(key, len(list(group))) for key, group in groupby(data))
print(compressed)
</code></pre>
<p>结果</p>
^{pr2}$
<p>这可能有助于了解这里发生了什么。在</p>
<pre><code>data = 'aaaabbсaa'
for key, group in groupby(data):
print(key, len(list(group)))
</code></pre>
<p>结果</p>
<pre><code>a 4
b 2
с 1
a 2
</code></pre>