Lesson 5 - Dictionaries and sets in C# .NET
In the previous lesson, Multidimentional arrays in C# .NET, we introduced, tried out linked lists, and then made a detour over to multi-dimensional arrays in C# .NET. Today's tutorial is going to be about dictionaries and sets.
Dictionaries
The idea of the dictionary is that we often need to access an element using a key. This concept works the same as with an array where the keys (indexes) are numeric. The dictionary allows us to index using any data type, e.g. a string. We then access the elements of the collection using these strings. An analogy can be found in a real paper dictionary where we have each string word associated with the translation, explanation, other meanings, etc.
The data in this collection is stored in a special way known as hashing. This approach allows us to
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In this tutorial, we'll introduce dictionaries and sets. We'll describe the Dictionary and HashSet classes and try them out on a few examples.
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