# 需求:三级菜单,b返回上级,q退出 provice = { "四川省": { "成都市": { "金牛区": { "茶店子": {}, "交大路": {} }, "青羊区": { "光华村": {}, "杜甫草堂": {} }, "锦江区": { "春熙路": {} }, "成华区": { "驷马桥": {} }, "武侯区": { "高升桥": {}, "红牌楼": {} }, "高新区": { "天府软件园": {}, "腾讯": {}, "IBM": {} } }, "宜宾市": { "翠屏区": {}, "长宁县": {}, "南溪区": {}, "江安县": {} } }, "北京市": { "东城区": { }, "朝阳区": { } } } last = [provice] current = provice while True: for i in current: print(i) choice = input("input:").strip() if len(choice) == 0: continue if choice in current: last.append(current) current = current[choice] if choice == "b": if last: current = last[-1] last.pop() if choice == "q": break