Advanced Dictionary Patterns

These patterns appear frequently in technical interviews and production code. Each demonstrates a clever way to use dictionaries to solve problems that would otherwise require slower, more complex approaches. Two-Sum Pattern Caching with Dictionaries Memoization is a technique where you cache function results to avoid redundant computation. Dictionaries are perfect for this: Graph Representation Dictionaries are the standard way to represent graphs in Python. Each key is a node, and the value is a list of connected nodes: State Machines Dictionaries can elegantly represent state transitions. The key is the current state, and the value is another dictionary mapping inputs to next states:

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