Dictionary
Explore how dictionaries in C# provide fast and efficient data access using unique keys instead of numeric indices. Learn to create, add, retrieve, and update key-value pairs with Dictionary<TKey, TValue> methods. Understand dictionary advantages over lists for large datasets and apply these concepts to real examples like counting character occurrences in text.
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We’ve explored collections like lists, stacks, and queues. While these are excellent for managing sequences of data, they rely on sequential ordering or numeric indices to retrieve items. But what if we need to look up a user’s profile using their email address, or find a product’s price using its barcode? Searching through a massive list item by item would be incredibly slow.
To solve this, .NET provides the dictionary. This collection is optimized for fast lookups using unique keys instead of numeric indices. Because dictionaries use hashing internally, retrieving a value by its key operates in