Head First Algorithms and Data Structures

Chapter 6. Serious data Structures: Hash Tables, Stacks, and Queues

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So far we’ve leaned on arrays and linked lists for our data structures. These are great basics, but not always the fastest way to find or organize things. Now we’re going straight to the heavy hitters. You’ll see how a hash table can find things almost instantly, no matter how big the collection gets; how a stack keeps things in last-in-first-out order (like a plate dispenser); and how a queue manages first-in-first-out tasks (like a coffee line). These structures are everywhere in real programs; once you know them, you’ll start spotting them hidden inside apps, tools, and even the systems you use every day.

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