Maps, Hash Tables, and Skip Lists
A map is an abstract data type designed to efficiently store and retrieve values based upon a uniquely identifying search key for each. Specifically, a map stores key-value pairs (k, v), which we call entries, where k is the key and v is its corresponding value. Keys are required to be unique, so that the association of keys to values defines a mapping. Figure 10.1 provides a conceptual illustration of a map using the file-cabinet metaphor. For a more modern metaphor, think about the web as being a map whose entries are the web pages. The key of a page is its URL (e.g., http://datastructures.net/) and its ...