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<b>Data Structures and Algorithms 
with Object-Oriented Design Patterns in C++</b><br>
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<H3><A NAME="SECTION002201000000000000000">Abstraction</A></H3>
<P>
Abstraction can be thought of as a mechanism for suppressing
irrelevant details while at the same time emphasizing relevant ones.
An important benefit of abstraction is that it makes it easier
for the programmer to think about the problem to be solved.
<P>
For example,
<em>procedural abstraction</em> lets the software designer
think about the actions to be performed
without worrying about how those actions are implemented.
Similarly,
<em>data abstraction</em> lets the software designer think about
the objects in a program and the interactions between those objects
without having to worry about how those objects are implemented.
<P>
There are also many different <em>levels of abstraction</em>.
The lower the levels of abstraction expose
more of the details of an implementation
whereas the higher levels hide more of the details.
<P>
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