Generate NFT attribute combinations with dedup and weighted random sampling

Problem You are generating NFT metadata. You are given K attribute categories (e.g., Ears, Eyes, Hat), each with a list of candidate values. Part A: Generate all combinations Generate all possible combinations by picking exactly one value from each category. Part B: Dedup Candidate lists may contain duplicate value strings within the same category. The output combinations must be deduplicated. Part C: Weighted random generation (follow-up) Each candidate value has a weight (non-negative int/float). Implement a function to generate one complete combination by independently sampling one value per category according to weights. Input (stdin) Line 1: integer K For each category: one line: category name name one line: integer M next M lines: value weight Output (stdout) First print the number of deduplicated combinations for Part A+B Then print all combinations, one per line, as comma-joined name=value in the input category order Finally print one line starting with RANDOM: followed by a randomly generated combination (Part C) Constraints 1 <= K <= 10 1 <= M <= 50 Full enumeration is only tested when the product of per-category unique counts is <= 2*10^5; otherwise only Part C is tested. Example Input: 2 Ears 2 Pointy 0.6 Wide 0.4 Eyes 3 Blue 1 Blue 1 Green 2 Output (ordering of combos may vary; random line is not fixed): 4 Ears=Pointy,Eyes=Blue Ears=Pointy,Eyes=Green Ears=Wide,Eyes=Blue Ears=Wide,Eyes=Green RANDOM: Ears=Wide,Eyes=Green Example Input 2 Ears 2 Pointy 0.6 Wide 0.4 Eyes 3 Blue 1 Blue 1 Green 2 Output 4 Ears=Pointy,Eyes=Blue Ears=Pointy,Eyes=Green Ears=Wide,Eyes=Blue Ears=Wide,Eyes=Green RANDOM: Ears=Pointy,Eyes=Blue