Implement Prototype(sizes []int,amount int) (int,error) by recursive choices without caching; Solve reuses smaller amounts in O(amount*len(sizes)) time and O(amount) space. Unlimited positive sizes; return minimum count for exact total, -1 if impossible. Zero amount returns zero, including empty sizes. Negative amount or nonpositive size returns error before search. Preserve input.
Edit exercise.go; retain the public types and signatures. prototype and final are separate stages. The executable tests recover panics as failures, report named checks, and exit nonzero on any failure. A successful run must execute at least one check. Tests use logical time or explicit synchronization where relevant.
Complete the starter code, then run the checks.
Results and errors will appear here.