Implement Prototype(items [][2]int,capacity int) (int,error) with subset enumeration; Solve uses O(nC) DP time and O(C) space. Items are (positive weight,nonnegative value); capacity is nonnegative. Each input position may be chosen once, including duplicate tuples as separate items. Empty selection is allowed. Invalid input returns error; preserve input. Totals fit int.
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.