What is the difference between `void f1(const Class &c)` and `void f2(Class const &c)`?
<p>What is the difference between these below functions ( Look at keyword <code>const</code> ) ?</p>

<pre><code>void f1(const Class &amp;c)
</code></pre>

<p>and</p>

<pre><code>void f2(Class const &amp;c)
</code></pre>
