擅长:python、mysql、java
<p>你在找<code>in</code></p>
<pre><code>if fields[0] in value:
</code></pre>
<p>但这不是一个非常有效的方法,因为它需要反复扫描dict值</p>
<p>您可以创建一个临时数据结构来帮助</p>
<pre><code>helper_dict = {k: v for v, x in myDict.items() for k in x}
</code></pre>
<p>所以你的代码变成</p>
<pre><code>helper_dict = {k: v for v, x in myDict.items() for k in x}
with open("input.txt") as f:
for line in f:
fields = line.split("\t")
key = fields[0]
if key in helper_dict:
newdict[helper_dict[key]] = len(myDict[helper_dict[key]])
</code></pre>