回答此问题可获得 20 贡献值,回答如果被采纳可获得 50 分。
<p>我正在做一个超级市场界面,我的程序工作正常,如果我不回去运行。但是,如果userchoice=2,我就不能返回userchoice=1。我只能去2或后面的选项。我想我的<code>while</code>循环可能有问题。你知道吗</p>
<pre><code>apples = 0
mangoes = 0
print("Welcome to the CS110 Supermarket!")
print("1. Potatoes ($0.75 per potato")
print("2. Tomatoes ($1.25 per tomato")
print("3. Apples ($0.5 per apple")
print("4. Mangoes ($1.75 per mango")
print("5. Checkout")
user_choice = int(input())
total = total + potatoes*0.75 + tomatoes*1.25 + apples*0.5 + mangoes*1.75
while user_choice == 1:
potatoes = int(input("How many potatoes?"))
total = total + potatoes*0.75
print("The total cost is $", total)
print("Welcome to the CS110 Supermarket!")
print("1. Potatoes ($0.75 per potato")
print("2. Tomatoes ($1.25 per tomato")
print("3. Apples ($0.5 per apple")
print("4. Mangoes ($1.75 per mango")
print("5. Checkout")
user_choice = int(input())
while user_choice == 2:
tomatoes = int(input("How many tomatoes?"))
total = total + tomatoes*1.25
print("The total cost is $", total)
print("Welcome to the CS110 Supermarket!")
print("1. Potatoes ($0.75 per potato")
print("2. Tomatoes ($1.25 per tomato")
print("3. Apples ($0.5 per apple")
print("4. Mangoes ($1.75 per mango")
print("5. Checkout")
user_choice = int(input())
while user_choice == 3:
apples=int(input("How many apples?"))
total = total + apples*0.5
print("The total cost is $", total)
print("Welcome to the CS110 Supermarket!")
print("1. Potatoes ($0.75 per potato")
print("2. Tomatoes ($1.25 per tomato")
print("3. Apples ($0.5 per apple")
print("4. Mangoes ($1.75 per mango")
print("5. Checkout")
user_choice = int(input())
while user_choice == 4:
mangoes = int(input("How many mangoes?"))
total = total + mangoes*1.75
print("The total cost is $",total)
print("Welcome to the CS110 Supermarket!")
print("1. Potatoes ($0.75 per potato")
print("2. Tomatoes ($1.25 per tomato")
print("3. Apples ($0.5 per apple")
print("4. Mangoes ($1.75 per mango")
print("5. Checkout")
user_choice=int(input())
if user_choice == 5:
print("The total cost is $",total)
pay = float(input("Please enter an amount to pay for the fruits and vegetables: "))
while pay < total:
pay = float(input("Please enter an amount more than payment: "))
change = pay - total
print("Your change will be $", change)
d5 = change // 5
d1 = (change % 5) // 1
quarter = ((change % 5) % 1) // 0.25
dime = (((change % 5) % 1) % 0.25) // 0.1
nickel = ((((change % 5) % 1) % 0.25) % 0.1) // 0.05
penny = (((((change % 5) % 1) % 0.25) % 0.1) % 0.05) // 0.01
print("Give the customer", d5, "$5 note,", d1, "$1 note,", quarter, "quarter,", dime, "dime,", nickel,"nickel,", penny, "penny.")
</code></pre>