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    <p><code>StudentEmployee</code> certainly is a subclass of <code>Person</code>. The problem is it is so <em>twice</em>: It indirectly inherits <code>Person</code> twice (once through <code>Student</code> and once through <code>Employee</code>) and that's why you get the "ambiguous base class" error. To make sure <code>StudentEmployee</code> only inherits <code>Person</code> once, you have to use <em>virtual inheritance</em>, like so:</p> <pre><code>class Person {}; class Student : public virtual Person {}; class Employee : public virtual Person {}; class StudentEmployee : public Student, public Employee {}; </code></pre> <p>This will fix your error.</p> <p>There is another big problem with your code, though, and it's called <em><a href="https://stackoverflow.com/questions/274626/what-is-the-slicing-problem-in-c">slicing</a></em>.</p> <p>When you do this:</p> <pre><code>Person ppl[3] = {pat, sam, em}; </code></pre> <p>An array of three <code>Person</code> objects will be created but those objects will be copy constructed using the implicitly defined copy constructor of the <code>Person</code> class. Now, the problem with this is that the objects in your array will be just <code>Person</code> objects and not objects of the subclasses you want them to be.</p> <p>To fix this, you'll have to make an array of pointers to <code>Person</code> objects, like this:</p> <pre><code>Person* ppl[] = {new Person("Pat"), new Student("Sam"), new Employee("Emily"), new StudentEmployee("Sienna")}; </code></pre> <p>or</p> <pre><code>Person* ppl[] = {&amp;pat, &amp;sam, &amp;em, &amp;sen}; </code></pre>
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    1. COBut, obviously, calling new like that will almost certainly lead to a memory leak
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    2. CO+1 for the slicing. And just in case bguiz didn't already know, this could also be Person* ppl[] = { &pat, &sam, &em, &sen }; - there is a slight difference in the memory management of these two options.
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    3. CO@Falmarri: Why? You still have the array of pointers.
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