Doubt:Keys and Satellite data

Each record contains a key, which is the value to be sorted, and the remainder of the record consists of satellite data, which are usually carried around with the key.

In a typical implementation of a dynamic set, each element is represented by an object whose fields can be examined and manipulated if we have a pointer to the object. Some kinds of dynamic sets assume that one of the object's fields is an identifying key field. If the keys are all different, we can think of the dynamic set as being a set of key values.

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