diff --git a/doc/index.html b/doc/index.html
index 46be860b..9558cd1a 100644
--- a/doc/index.html
+++ b/doc/index.html
@@ -1380,7 +1380,7 @@ <h2 id="_main_parameter">5. Main parameter</h2>
 </div>
 <div class="listingblock">
 <div class="content">
-<pre class="prettyprint highlight"><code class="language-bash" data-lang="bash">$ java Main -debug file1 file2</code></pre>
+<pre class="prettyprint highlight"><code class="language-bash" data-lang="bash">$ java Main -debug 2 file1 file2</code></pre>
 </div>
 </div>
 <div class="paragraph">
@@ -2123,4 +2123,4 @@ <h2 id="_download">29. Download</h2>
 <script src="https://cdnjs.cloudflare.com/ajax/libs/prettify/r298/prettify.min.js"></script>
 <script>prettyPrint()</script>
 </body>
-</html>
\ No newline at end of file
+</html>