Python递归深度超限报错原因及修复方案咨询

报错原因 #

你遇到的maximum recursion depth exceeded错误，根源在calculate_total_cost函数，而非你推测的display_budget_summary：

• 函数内部直接调用了自身calculate_total_cost(hotels, flights)，且没有任何终止条件，导致函数无限递归调用，直到触及Python的递归深度上限
• 总费用计算逻辑存在bug：sum({h_cost, f_cost})使用了集合，集合会自动去重，若酒店总费用和机票总费用相等，会被只统计一次，完全不符合预算统计需求

具体修复方案 #

1. 移除无限递归调用：在calculate_total_cost中直接返回计算好的总费用，不要调用自身
2. 修正总费用计算：将sum({h_cost, f_cost})改为h_cost + f_cost，直接相加两类费用的总和
3. 清理冗余代码：删除函数内无用的global声明（函数已通过参数接收hotels和flights，无需全局变量），以及add_destination中未使用的cost变量
4. 完善函数返回值：让calculate_total_cost明确返回总费用，确保display_budget_summary能拿到正确结果

修正后的完整代码 #

cities = ["Boston", "Las Vegas", "Porto Alegre", "Cape Town", "Berlin", "Okinawa", "Sydney"]
hotels = [255, 450, 150, 250, 650, 675, 850]
flights = [950, 3000, 4500, 2750, 2500, 3500, 10500]


def add_destination(city, hotel, flight):
    global cities, flights, hotels
    print("""Add your desired destination. Please include your hotel and flight cost,
    as well as the name of your desired location and hotel.""")
    new_place_city = input("Please type your new city: ")
    new_place_hotel = int(input("Please type your new hotel's price per night: "))
    new_place_flight = int(input("Please type the cost of your flight:"))
    cities.append(new_place_city)
    hotels.append(new_place_hotel)
    flights.append(new_place_flight)


def calculate_total_cost(hotels, flights):
    f_cost = sum(flights)
    h_cost = sum(hotels)
    t_cost = h_cost + f_cost
    return t_cost


def display_budget_summary(cities, hotels, flights):
    for i in range(len(cities)):
        print(f"{cities[i]}, ${hotels[i]} ${flights[i]}.")
    result = calculate_total_cost(hotels, flights)
    print(f"Your current budget/money spent is ${result}.")


while True:
    print(f"""Currently, the cities you plan to visit during your vacation are {cities}."
    Please choose an option to make any edits to your vacation.""")
    print("1. Add a destination")
    print("2. View budget summary")
    print("3. Exit program")

    option = int(input("Please choose an answer: "))

    if option == 1:
        add_destination(cities, hotels, flights)

    elif option == 2:
        display_budget_summary(cities, hotels, flights)

    elif option == 3:
        break

    else:
        print("Please choose a valid option.")

内容的提问来源于stack exchange，提问作者Declan Kennedy