day3-三级目录

date = {"guangdong":{"guangzhou":{"tianhe":["tyx","zjxc"],
                                  "panyu":["a","b"]},
                     "maoming":{},
                     "zhongshan":{}},
        "henan":{"jiaozuo":{"boai":["nan","bei"],
                            "wen":["c","d"]},
                 "zhengzhou":{},
                 "luoyang":{}},
        "shandong":{"jinan":{},
                    "qingdao":{}}}
exit_flag = True
while exit_flag:
    for i in date:
        print(i)
    choice = input("please choose")
    if choice in date:
        while exit_flag:
            for i2 in date[choice]:
                print(i2)
            choice2 = input("please choose2")
            if choice2 in date[choice]:
                while exit_flag:
                    for i3 in date[choice][choice2]:
                        print(i3)
                    choice3 = input("please choose3")
                    if choice3 in date[choice][choice2]:
                        for i4 in date[choice][choice2][choice3]:
                            print(i4)
                        choice4 = input("Ending!Return please press 'b'.")
                        if choice4 == "b":
                            pass
                        elif choice4 == "q":
                            exit_flag = False
                    if choice3 == "b":
                         break
                    elif choice3 == "q":
                         exit_flag = False
            if choice2 == "b":
                break
            elif choice2 == "q": 
                exit_flag = False