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Memoize

MediumP1Coding

Implement memoize(fn).

It returns a function that caches results. If it is called again with the same arguments, return the cached result without calling fn again.

Two calls have the same arguments when they pass the same number of arguments and each pair is the same value by ===. Cache undefined and other falsy results too. this must be forwarded to fn.

The returned function has a cache property that is the underlying Map.

Example 1

Input
const f = memoize(slowSquare); f(4); f(4);
Output
slowSquare runs once
Why
The second call is served from the cache.

Constraints

  • Arguments are primitives or object references.
  • Argument order matters: f(1, 2) and f(2, 1) are different calls.

Hints

Run checks the 3 visible tests, Submit all 9.