概要信息：

problem_dict = {
    "诗仙是谁": "李白",
    "中国第一个朝代": "夏朝",
    "三十六计的第一计是什么": "瞒天过海",
    "天府之国是中国的哪个地方": "四川",
    "中国第一长河": "长江"
}

work = True
flag = "c"

def train(arg_question, arg_answer):
    problem_dict[arg_question] = arg_answer
    print(f"小智：训练成功，我现在会回答{len(problem_dict)}个问题了！")
    print("--------------------")
    num = 1
    for key in problem_dict.keys():
        print(str(num) + "、" + key)
        num += 1
    print("--------------------")

def exchange(words):
    global work
    ...