如何在Python中从用户输入的游戏列表获取对应单价并计算总价

你需要通过选中的游戏名称找到它在game_titles列表中的索引，再用该索引获取game_prices中对应的单价。另外要注意，当前你存入game_prices的是字符串类型，必须先转换成数值类型（比如float）才能进行乘法运算。

关键修改步骤 #

1. 修正价格输入的类型转换
   在输入价格时，直接将输入内容转为float类型，避免后续计算出错：

   print('Enter the price of each game (followed by ENTER on the keyboard):')
   for i in range(0, n):
       input_prices = float(input('$'))  # 转换为浮点型
       game_prices.append(input_prices) 
   

2. 获取对应游戏单价并计算总价
   在倒数第二行的位置，先通过index()方法找到游戏的索引，再取出对应单价计算总价：

   # 获取选中游戏的索引
   game_index = game_titles.index(game_to_purchase)
   # 计算总价
   total_price = num_copies * game_prices[game_index]
   

3. 修复库存打印逻辑
   你原来的库存打印循环存在索引越界问题，改成以下方式可正确垂直展示每个游戏和价格：

   print('\nGAMES IN STOCK')
   for title, price in zip(game_titles, game_prices):
       print(f"{title} ${price:.2f}")
   

4. 优化总价输出格式
   将总价格式化为两位小数，符合货币展示习惯：

   print(f'The total for {num_copies} of {game_to_purchase} is ${total_price:.2f}')
   

完整修正代码 #

# creating an empty list
game_titles = []
game_prices = []
 
# number of elements as input
n = int(input("Enter number of game titles (followed by ENTER on the keyboard): "))

# iterating till the range
print('Enter the name of each game (followed by ENTER on the keyboard):')
for i in range(0, n):
    input_names = input()
    # adding the element
    game_titles.append(input_names) 
    
print('Enter the price of each game (followed by ENTER on the keyboard):')
for i in range(0, n):
    input_prices = float(input('$'))  # 转换为浮点型
    game_prices.append(input_prices) 
    
print('\nGAMES IN STOCK')
# 正确打印每个游戏和对应价格
for title, price in zip(game_titles, game_prices):
    print(f"{title} ${price:.2f}")
    
while True:
    try:
        game_to_purchase = str(input("Please enter the name of the game you would like to purchase: "))
    except ValueError:
        print("Sorry, that game is not in stock. Please enter a game that is in stock:")
        continue

    if game_to_purchase not in game_titles:
        print("Sorry, that game is not in stock.\n")
        continue
    else:
        break

while True:
    try:
        num_copies = int(input("Please enter the number of copies you would like to purchase (1-10): "))
    except ValueError:
        print("Sorry, that was an invalid input. Please try again.")
        continue

    if num_copies > 10 or num_copies < 1:  # 补充判断小于1的情况
        print("Sorry, please enter a number between 1 and 10.\n")
        continue
    else:
        break
    
# 获取对应游戏的单价并计算总价
game_index = game_titles.index(game_to_purchase)
total_price = num_copies * game_prices[game_index]
# 格式化输出总价
print(f'The total for {num_copies} of {game_to_purchase} is ${total_price:.2f}')

额外补充：在购买数量的判断中，新增了对小于1的输入限制，避免用户输入0或负数。

内容的提问来源于stack exchange，提问作者Spencer