nd... still gives us an error. -->

<p>そうすると...
まだ、エラーがでます。</p>

<pre><code class="language-text">&lt;anon&gt;:11:24 error: cannot borrow immutable borrowed content as mutable
&lt;anon&gt;:11                    data[i] += 1;
                             ^~~~
</code></pre>

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