mcs方法第三方胜多负少的way

# -*- coding: utf-8 -*- all_extracts=["B", "C", "D", "G", "I", "S", "T"] singleton_extracts = ["B", "G", "D"] combination_extracts = ["I", "S", "C"] mix_rules_source = [("B", "G"), ("B", "D"), ("D", "G"), ("I", "S"), ("C", "S"), ("C", "I")] # initialize:"B"+"G" -> "S" mix_rules_target = ["S", "I", "C", "B", "G", "D"] #initialize mix_to_result = {} for i in range(len(all_extracts)): for j in range(i, len(all_extracts)): mix_to_result[(all_extracts[i], all_extracts[j])] = "" for src, trg in mix_to_result.items(): """generate mix rules""" first_type, second_type = src if first_type > second_type: # first_type letter should small than second_type :: "C","B" -> "B","C" first_type, second_type = second_type, first_type assert (first_type, second_type) in mix_to_result mix_result = "T" if second_type == "T": mix_result = first_type if (first_type, second_type) in mix_rules_source: mix_result = mix_rules_target[mix_rules_source.index((first_type, second_type))] if first_type == second_type : mix_result = first_type mix_to_result[(first_type, second_type)] = mix_result def mix_process(state): """process mix state""" if len(state) == 1: return state[0] while len(state) > 1: for i in range(len(state)-1): first_type, second_type = state[i] , state[i+1] if first_type > second_type: # first_type letter should small than second_type :: "C","B" -> "B","C" first_type, second_type = second_type, first_type mix_result = mix_to_result[(first_type, second_type)] state[i] = mix_result del state[-1] return state[0] inputs = str(input()) state = [i for i in inputs.strip()] # list type print(mix_process(state))