comma operators in c++
<pre><code>int main() {
   int x = 6;
   x = x+2, ++x, x-4, ++x, x+5;
   std::cout &lt;&lt; x;
}

// Output: 10
</code></pre>

<hr>

<pre><code>int main() {
   int x = 6;
   x = (x+2, ++x, x-4, ++x, x+5);
   std::cout &lt;&lt; x;
}

// Output: 13
</code></pre>

<hr>

<p>Please explain.</p>
