Implementing a linked list

A linked list is where one list contains keys that point to keys in another list. An analogy, in database terms, would be where you have a table that contains data, and a separate index that points to the data. One index might produce a list of items by ID. Another index might yield a list according to title and so on. The salient feature of the linked list is that you do not have to touch the original list of items.

For example, in the diagram shown next, the primary list contains ID numbers and the names of fruits. If you were to directly output the primary list, the fruit names would display in this order: Apple, Grape, Banana, Orange, Cherry. If you were to use the linked list as an index, on the other hand, the resulting ...

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