你如何只允許列表中的輸入？ （蟒蛇自動售貨機）

Question

我需要編寫一個自動售貨機，只接受某些硬幣

「它可以讓你輸入1P，2P，5P，10便士，20便士，50便士和£1.00，但它會拒絕£2.00硬幣」

我有一個列表，裏面浮點值：

coins = ["0.01","0.02","0.05","0.10","0.20","0.50","1"] 

這些都是硬幣，那我想用戶進入

coin = float(input()) 

並在此之後我有

def balance(): 
    coin = float(input("Please enter your coins.")) 
    if coin not in coins: 
      print("Incorrect coin amount! Please remember we don't accept 2 pound coins!") 

    else: 
     print("Correct coin amount. The coins have been added to your balance") 
     fb = fb + coin 

我不能得到這個工作，因爲這將只是打印「不正確的硬幣量！請記住，我們不接受2磅硬幣！「。 在此之後，我嘗試了這個解決方案已經在這裏：Python Coding - Vending machine - How to get the user to only enter certain coins? 我認爲這意味着我需要改變我的浮動（輸入（））和一切浮動爲int，所以改變0.01（1P）至1。但是，當我這樣做，我還是老樣子得到

'int' object has no attribute 'split' 

當該代碼使用它

dict = {"KitKat":"80p", "Coca-Cola":"85p", "DairyMilk":"80p","Walkers Crisps":"90p"} 
coins = ["1","2","5","10","20","50","100"] 

def balance(): 
    inp = int(input("Please enter your coins. Please enter in pence, for example 1 pound = 100")) 
    if any(int(coin) not in value for coin in inp.split()): 
     print("Machine doesn't accept these coins") 


else: 
    print("Correct coin amount. The coins have been added to your balance") 
    fb = fb + coin 


def items(): 
    print (" 1. KitKat:" , dict['KitKat']) 
    print (" 2. Coca-Cola:", dict['Coca-Cola']) 
    print (" 3. Dairy Milk:", dict["DairyMilk"]) 
    print (" 4. Walkers Crisps:", dict["Walkers Crisps"]) 
snack = 1 # need a while loop, ignore 
fb = 0.00 
balance() 
print("Your full balance is",fb) 

Answer 1

我建議轉換英鎊便士，所以你不必做浮動數學運算，只要你顯示數值就轉換回來，你也可以使用decimal這個模塊，b讓我們不要太參與到這一點。您的最終問題似乎是您正在比較不同類型的值，並且1 != "1"。我們先排序。

coins = [1, 2, 5, 10, 20, 50, 100] # pence 
coin_in = int(input("Enter amount (in pence): ")) 

if coin_in not in coins: 
    # incorrect input, handle it