Is copy constructor called if assignment operator wasn't defined?
<p>Suppose that the <code>foo</code> class does not have an overloaded assignment operator. What happens when an assignment <code>a = b;</code> is given for two <code>foo</code> objects?
options are:</p>

<ol>
<li>The automatic assignment operator is used</li>
<li>The copy constructor </li>
</ol>
