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MediumPro challengePythonJavaScriptTypeScript

Memoize

FunctionsPatternsObjects

Implement memoize(fn) returning a wrapper that caches the result of fn
per argument vector. Subsequent calls with the same arguments must skip
the underlying fn and serve the cached result instead.

Requirements

  • Support arbitrary arity (zero or more arguments).
  • Argument equality must be structural ([1,2] and [1,2] hit the same

cache entry; [1,2] and [1,3] don't).

  • Don't recompute on cache hit — the test suite verifies the underlying

function is invoked at most once per unique argument vector.

The provided solve(callArgs) drives your implementation through a sequence
of calls and reports how many times the underlying expensive function ran.

Sample tests

Test #1Same single argument repeated → 1 underlying call
Input: [[[1],[1],[1]]]
Output: {"calls":1,"results":[1,1,1]}
Test #2Distinct arguments → as many underlying calls
Input: [[[1],[2],[3]]]
Output: {"calls":3,"results":[1,2,3]}
Test #3Alternating repeats stay cached
Input: [[[5],[10],[5],[10],[5],[10]]]
Output: {"calls":2,"results":[5,10,5,10,5,10]}
Test #4Multi-arg — vector equality, not first-arg only
Input: [[[1,2],[1,2],[3,4]]]
Output: {"calls":2,"results":[3,3,7]}
Test #5No calls → no underlying invocation
Input: [[]]
Output: {"calls":0,"results":[]}
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