擅长：python、mysql、java
<p>您可以尝试使用<code>itertools.groupby</code>：</p>
<pre><code>s = 'aaaabbсaa'
from itertools import groupby
result=''.join(f'{label}{len(list(group))}' for label, group in groupby(s))
#same as:
#result = [f'{label}{len(list(group))}' for label, group in groupby(s)]
#result=''.join(result)
</code></pre>
<p>输出：</p>
<pre><code>result
'a4b2с1a2'
</code></pre>
