注意项
<h2>切片的坑</h2>
<ol>
<li>
<p>引用后，可能对原值有影响</p>
<p><img src="https://www.showdoc.com.cn/server/api/attachment/visitFile?sign=c6a87c35574cd386c780225cb2d8cedf" alt="" /></p>
</li>
<li>
<p>循环变量，似乎是同一个</p>
<p><img src="https://www.showdoc.com.cn/server/api/attachment/visitFile?sign=2cebe5842aba445c200badf10c4d091d&amp;file=file.png" alt="" /></p>
<p><img src="https://www.showdoc.com.cn/server/api/attachment/visitFile?sign=4ba16992230d3baff59155e2320bfee3&amp;file=file.png" alt="" /></p>
</li>
</ol>