如何停止循环，直到用户输入关键字停止？

Question

我的代码现在处于一个无限循环中，显示甜甜圈的菜单选项。我想让用户选择任意多的甜甜圈，直到他们输入“5”。你知道吗

这是我的密码：

print("Welcome to Dino's International Doughnut Shoppe!")
name = input("Please enter your name to begin: ")

#doughnuts menu
loop = 0
while loop == 0:
    choice = 0
    while choice not in [1,2,3,4]:
        print("Please enter a valid choice from 1-4.")
        print("Please select a doughnut from the following menu: ")
        print("1. Chocolate-dipped Maple Puff ($3.50 each)")
        print("2. Strawberry Twizzler ($2.25 each)")
        print("3. Vanilla Chai Strudel ($4.05 each)")
        print("4. Honey-drizzled Lemon Dutchie ($1.99)")
        print("5. No more doughnuts.")
        choice = int(input(">"))


if choice == 1:
    chocolate = int(input("How many chocolate-dipped Maple Puff(s) would you like to purchase? "))
elif choice == 2:
    strawberry = int(input("How many Strawberry Twizzler(s) would you like to purchase? "))
elif choice == 3:
    vanilla = int(input("How many Vanilla Chai Strudel(s) would you like to purchase? "))
elif choice == 4:
    honey = int(input("How many Honey-drizzled Lemon Dutchie(s) would you like to purchase? "))
elif choice == 5:
    print(f"{name}, Here is your receipt: ")

    if choice == 1:
        print("==========================================")
        print(f"{chocolate} Chocolate Dipped Maple Puffs")
        print("==========================================")
        print(f"Total Cost: ${chocolate*3.50:.2f}")
    elif choice == 2:
        print("==========================================")
        print(f"{strawberry} Strawberry Twizzlers")
        print("==========================================")
        print(f"Total Cost: ${strawberry*2.25:.2f}")
    elif choice == 3:
        print("==========================================")
        print(f"{vanilla} Vanilla Chai Strudels")
        print("==========================================")
        print(f"Total Cost: ${vanilla*4.05:.2f}")
    elif choice == 4:
        print("==========================================")
        print(f"{honey} Honey-drizzled Lemon Dutchies")
        print("==========================================")
        print(f"Total Cost: ${honey*1.99:.2f}")

print("Thank you for shopping at Dino's International Doughnut Shoppe! Please come again!")

所以现在代码只会连续显示甜甜圈菜单，但是我希望当输入5时，它会转到数学计算/代码结尾。你知道吗

Answer 1

这里有一些问题。你知道吗

第一个是响应选择的逻辑在while循环之外。可以通过缩进整块来固定。你知道吗

第二，当用户输入5时，while choice not in [1,2,3,4]:中的条件计算为True，因此提示用户再次输入有效的选项。这可以通过完全移除内部while循环来解决。你知道吗

最后，在到达elif choice == 5块时，用户将看不到这些收据打印中的任何一个，因为choice是5，因此不是1、2、3或4。我想你这里的意思是chocolate、strawberry、vanilla或honey的计数为非零。而且这些都应该是if而不是elif块，因为它们相互独立（用户可以得到一些巧克力和香草）。你知道吗

考虑到所有这些，这里是一个重构：

print("Welcome to Dino's International Doughnut Shoppe!")
name = input("Please enter your name to begin: ")

#doughnuts menu
chocolate = strawberry = vanilla = honey = 0
done = False
while not done:
    print("Please enter a valid choice from 1-4.")
    print("Please select a doughnut from the following menu: ")
    print("1. Chocolate-dipped Maple Puff ($3.50 each)")
    print("2. Strawberry Twizzler ($2.25 each)")
    print("3. Vanilla Chai Strudel ($4.05 each)")
    print("4. Honey-drizzled Lemon Dutchie ($1.99)")
    print("5. No more doughnuts.")
    choice = int(input(">"))


    if choice == 1:
        chocolate = int(input("How many chocolate-dipped Maple Puff(s) would you like to purchase? "))
    elif choice == 2:
        strawberry = int(input("How many Strawberry Twizzler(s) would you like to purchase? "))
    elif choice == 3:
        vanilla = int(input("How many Vanilla Chai Strudel(s) would you like to purchase? "))
    elif choice == 4:
        honey = int(input("How many Honey-drizzled Lemon Dutchie(s) would you like to purchase? "))
    elif choice == 5:
        done = True
        print(f"{name}, Here is your receipt: ")

        if chocolate > 1:
            print("==========================================")
            print(f"{chocolate} Chocolate Dipped Maple Puffs")
            print("==========================================")
            print(f"Total Cost: ${chocolate*3.50:.2f}")
        if strawberry > 1:
            print("==========================================")
            print(f"{strawberry} Strawberry Twizzlers")
            print("==========================================")
            print(f"Total Cost: ${strawberry*2.25:.2f}")
        if vanilla > 1:
            print("==========================================")
            print(f"{vanilla} Vanilla Chai Strudels")
            print("==========================================")
            print(f"Total Cost: ${vanilla*4.05:.2f}")
        if honey > 1:
            print("==========================================")
            print(f"{honey} Honey-drizzled Lemon Dutchies")
            print("==========================================")
            print(f"Total Cost: ${honey*1.99:.2f}")

    print("Thank you for shopping at Dino's International Doughnut Shoppe! Please come again!")