# Implement memoized Fibonacci using a dictionary cache

Canonical URL: <https://datadriven.io/problems/implement-memoized-fibonacci-using-a-dictionary-cache-defin-e6f1bf3c>

Domain: Python · Difficulty: medium

## Problem

Implement memoized Fibonacci using a dictionary cache. Define fib(n) that checks the cache before computing. Print fib(10) and fib(20).

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