Python 练习：三级菜单选择城市(二)

优化了上一个三级菜单选择城：http://www.cnblogs.com/klvchen/p/8646466.html

info = {

    'GuangDong':{

        'GuangZhou': ['TianHe', 'HaiZhu'],

        'MaoMing': ['MaoNan', 'DianBai']},

    'ShanDong': {

        'JiNan': ['ShiZhong', 'LiXia'],

        'QingDao': ['ShiNan', 'ShiBei']

    },

    'GuangXi': {

        'NanNin': ['WuNing', 'LongAn'],

        'GuiLing': ['YangSuo', 'QuanZhou']

    }

}

parent_list = []

current_layer = info

while True:

    for key in current_layer:

        print(key)

    choiced = input("Please select: [ b: back | q: exit]")

    if choiced in current_layer:

        parent_list.append(current_layer)

        try:

            current_layer = current_layer[choiced]

        except:

            print("This is last level")

            current_layer = parent_list.pop()

            continue

    elif choiced == "b":

        if parent_list:

            current_layer = parent_list.pop()

    elif choiced == "q":

        break

    else:

        print("Please input right optional.")

        continue

运行结果：