运费计算器没有产生正确的结果

Question

以下是运行程序的示例： 欢迎使用 Fast Freight Shipping Company 运费程序。 该程序旨在以磅为单位计算您的包裹重量，并根据以下费率计算运输它们的成本。

2 pounds or less = $1.10 per pound
Over 2 pounds but not more than 6 pounds = $2.20 per pound
Over 6 pounds but not more than 10 pounds = $3.70 per pound
Over 10 pounds = $3.80 per pound

Please enter your package weight in pounds: 1
Your cost is: $ 1.10
Would you like to ship another package <y/n>? y
Please enter your package weight in pounds: 5
Your cost is: $ 11.00
Would you like to ship another package <y/n>? y
Please enter your package weight in pounds: 52
Your cost is: $ 197.60
Would you like to ship another package <y/n>? y
Please enter your package weight in pounds: 8
Your cost is: $ 29.60
Would you like to ship another package <y/n>? y
Please enter your package weight in pounds: 3
Your cost is: $ 6.60
Would you like to ship another package <y/n>? t
Invalid Input
Would you like to ship another package <y/n>? y
Please enter your package weight in pounds: 10
Your cost is: $ 37.00
Would you like to ship another package <y/n>? n
Thank you for your purchase, your total charge is $ 282.90 
Goodbye!

这是我到目前为止所拥有的：

charges = 0
answer = "yes"

while (answer == "yes"):
 packageWeight = eval (input ("Enter weight of package: "))
 answer = input ("Do you have more items to input? <yes/no>? ")

 if (packageWeight <=2):
     charges = (packageWeight * 1.10)
     print ("The cost is: $",charges)
 elif (packageWeight >2) and (packageWeight<=6):
     charges= (packageWeight * 2.20)
     print ("The cost is: $", charges)
 elif (packageWeight >6)and (packageWeight<=10):
     charges = (packageWeight * 3.70)
     print ("The cost is: $", charges)
 else :
     charges = (packageWeight * 3.80)
     print ("The cost is: $", charges)

message = "Thank you for your purchase, your total charge is $"
sum= charges+charges
message += format(sum, ',.2f')

print(message)
print("Goodbye!")

我如何找到所有费用的总和？ 我如何才能在成本之后提出第二个问题？

So it would display:
Enter weight of package: 3
The cost is: 6.60
Do you have more items to input? yes/no

Answer 1

我不太明白这个陈述how would I find the sum of all charges ，但我解决了你的第二个问题。

这是代码：

def get_charges(current_weight):
    if (current_weight <= 2):
        return (current_weight * 1.10)
    elif (current_weight > 2) and (current_weight <= 6):
        return (current_weight * 2.20)
    elif (current_weight > 6) and (current_weight <= 10):
        return (current_weight * 3.70)
    else:
        return (current_weight * 3.80)


charges = 0
answer = "yes"

while (answer == "yes"):
    # Eval is not recommended, use a float and round if needed.
    packageWeight = float(input("Enter weight of package: "))
    charges += get_charges(packageWeight)
    print("Current charges: ", charges)
    answer = input("Do you have more items to input? <yes/no>? ")


print(f"Thank you for your purchase, your total charge is ${charges}")
print("Goodbye!")

出于安全原因不推荐eval()，所以我把它改成了float()。

如果您有任何问题，请告诉我