menu = {

    '北京': {

        '海淀': {

            '五道口': {

                'soho': {},

                '网易': {},

                'google': {}

            },

            '中关村': {

                '爱奇艺': {},

                '汽车之家': {},

                'youku': {},

            },

            '上地': {

                '百度': {},

            },

        },

        '昌平': {

            '沙河': {

                '老男孩': {},

                '北航': {},

            },

            '天通苑': {},

            '回龙观': {},

        },

        '朝阳': {},

        '东城': {},

    },

    '上海': {

        '闵行': {

            "人民广场": {

                '炸鸡店': {}

            }

        },

        '闸北': {

            '火车站': {

                '携程': {}

            }

        },

        '浦东': {},

    },

    '山东': {},

}

last_menu = []

current_menu = menu

while True:

    for key in current_menu:

        print(key)

    choice = input(">:").strip()

    if not choice: continue

    if choice in current_menu:

        last_menu.append(current_menu)

        current_menu = current_menu[choice]

    if choice == "q":

        if last_menu:

            current_menu = last_menu.pop()

        else:

            print("已经是最顶层")

    if choice == "Q":

        current_menu = menu
最多再加个输入错误重新输入。 最多也就这点代码。