Lesson 3 - Dictionaries in Swift
In the previous lesson, Filtering and mapping arrays in Swift, we discussed advanced array methods.
In today's Swift tutorial, we're going to leave arrays and introduce dictionaries.
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 arrays 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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