1.單次增加一級節點

db = {

}
v = input(">>>")
db[v] = {}
print(db)

2.無限迴圈的來增加一級節點

db = {

}
while True:
    v = input(">>>")
    db[v] = {}
    print(db)

3.完善

db = {
    "上海": {},
    "北京":{
        "昌平":{
            "沙河":{},
            "回龍觀":{},
        },
        "朝陽"
 
:{},
        "海淀":{},
    }
}
path = []
while True:
    temp = db
    for item in path:
        temp = temp[item]
    print("當前可選的所有子節點：", list(temp.keys()))

    choice = input('1:新增節點；2：檢視節點（b/q)；\n >>>')
    if choice == "1":
        name = input("請輸入要新增的節點名稱：")
        temp[name] = {}
    
 
elif choice == "2":
        name = input("請輸入要檢視的節點名稱：")
        path.append(name)
    elif choice.lower() == "b":
        if path:                 #if path == True:
            path.pop()
    elif choice.lower() == "q":
        print(temp)          #輸出當前字典後再退出
        break
    else:
        print("
 
輸入錯誤，請重新輸入！")