In computer science's object-oriented programming, the mapped relationships of sub- and superclasses is known as a hierarchy. This can be visualized as an upside-down tree (or perhaps a pyramid), the top of which is known as the root. An exception is C++, where no single root class exists. The issue is more complicated with languages that support multiple inheritance, where hierarchy can be any directed acyclic graph.
Aggregation or composition r...
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Hierarchy
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