#!/usr/bin/env python
data = {
    '北京':{
        "昌平":{
            "沙河":["oldboy","test"],
            "天通苑":["链家地产","我爱我家"]
        },
        "朝阳":{
            "望京":["奔驰","陌陌"],
            "国贸":{"CICC","HP"},
            "东直门":{"Advent","飞信"},
        },
        "海淀":{},
    },
    '山东':{
        "德州":{},
        "青岛":{},
        "济南":{}
    },
    '广东':{
        "东莞":{},
        "常熟":{},
        "佛山":{},
    },
}
exit_flag = False
while not exit_flag:
    for i in data:
        print(i)
    choice =input('选择进入>>')
    if choice  in data:
        while not exit_flag:
            for i2 in data[choice]:
                print('\t',i2)
            choice2 = input('选择进入2>>')
            if choice2 in data[choice]:
                while not exit_flag:
                    for i3 in data[choice][choice2]:
                        print("\t",i3)
                    choice3 = input('选择进入3>>')
                    if choice3 in data[choice][choice2]:
                        while not exit_flag:
                            for i4 in data[choice][choice2][choice3]:
                                print(i4)
                            choice4 = input('最后一层,按B返回>>')
                            if choice4 == 'b':
                                break
                            elif choice4 =='q':
                                exit_flag =True
                    if choice3 == 'b':
                        break
                    elif choice3 == 'q':
                        exit_flag = True
            if choice2 == 'b':
                break
            elif choice2 == 'q':
                exit_flag = True