Interview Cake
Array
Stores things in order. Has quick lookups by index.
Dynamic Array
An array that automatically grows as you add more items.
Linked List
Also stores things in order. Faster insertions and deletions than arrays, but slower lookups (you have to "walk down" the whole list).
Queue
Like the line outside a busy restaurant. "First come, first served."
Stack
Like a stack of dirty plates in the sink. The first one you take off the top is the last one you put down.
Hash Table
Like an array, except instead of indices you can set arbitrary keys for each value.
Tree
Good for storing hierarchies. Each node can have "child" nodes.
Binary Search Tree
Everything in the left subtree is smaller than the current node, everything in the right subtree is larger. lookups, but only if the tree is balanced!
Graph
Good for storing networks, geography, social relationships, etc.
Trie
Stores a set of strings in a big tree of characters. Good for lookups by prefix. Sometimes saves space.
Heap
A binary tree where the smallest value is always at the top. Use it to implement a priority queue.
Priority Queue
A queue where items are ordered by priority.
Bloom filter
A constant-space bitmap that lets you quickly check whether or not an item is in a set. Can give false positives.
LRU Cache
Lets you quickly identify which item hasn't been used for the longest amount of time.
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