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In this video, we'll
see a simple example of

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multiple inheritance in c++.

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Multiple inheritance occurs when a
derived class inherits from two or

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more base classes at the same time.

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The base classes may belong to
unrelated class hierarchies.

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The class diagram on the right shows
an example of multiple inheritance.

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In this case, the class department
chair is derived from both

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faculty and administrator classes.

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So if we use public inheritance,
then a department chair is a

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faculty member and a department
chair is also an administrator.

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The c++ syntax for multiple
inheritance is simple.

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We declare our derived class and then
provide a comma separated list of the

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base classes that it's derived from.

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In this case, department chair is
our derived class, and its base

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classes are faculty and administrator.

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We're only showing public inheritance
here, but we could also use the

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other types of c++ inheritance.

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Multiple inheritance is beyond the
scope of this course, and it can

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be very, very complex in practice.

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There are some compelling use
cases for multiple inheritance.

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However, in many cases we can refactor
our design so that the multiple

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inheritance can be avoided, and many
times we end up with a better design.

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This isn't because there's anything
wrong with multiple inheritance.

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The problem with multiple inheritance
is that because it can be so complex,

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many developers don't fully understand
it, and, therefore, may misuse it.

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More often, you see multiple
inheritance in class libraries and

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frameworks that you might be using.