Question

我正在尝试使用python创建一个计算运费的程序。

但是，我无法将程序运行到正常工作的位置。

我的总金额相同，美国为6美元，加拿大为8美元。我似乎无法通过那个。

total = raw_input('What is the total amount for your online shopping?')
country = raw_input('Shipping within the US or Canada?')

if country == "US":
    if total <= "50":
        print "Shipping Costs $6.00"
    elif total <= "100":
            print "Shipping Costs $9.00"
    elif total <= "150":
            print "Shipping Costs $12.00"
    else:
        print "FREE"

if country == "Canada":
    if total <= "50":
        print "Shipping Costs $8.00"
    elif total <= "100":
        print "Shipping Costs $12.00"
    elif total <= "150":
        print "Shipping Costs $15.00"
    else:
        print "FREE"

Answer 1

你应该从raw_input获得整数，而不是字符串。使用int()。
比较值，如50,100,150，......也应为integer。

是固定代码。

total = int(raw_input('What is the total amount for your online shopping?'))
country = raw_input('Shipping within the US or Canada?')

if country == "US":
    if total <= 50:
        print "Shipping Costs $6.00"
    elif total <= 100:
        print "Shipping Costs $9.00"   # improved indentation
    elif total <= 150:
        print "Shipping Costs $12.00"  # improved indentation
    else:
        print "FREE"

if country == "Canada":
    if total <= 50:
        print "Shipping Costs $8.00"
    elif total <= 100:
        print "Shipping Costs $12.00"
    elif total <= 150:
        print "Shipping Costs $15.00"
    else:
        print "FREE"

Answer 2

你不能用数字比较字符串。而是首先转换为int然后进行比较。

例如：

if int(total) < 50

避免重复的变量也会有所帮助。

Answer 3

您正在以数字方式比较字符串。这是不可能的，例如将apple与orange进行比较，哪一个更大？计算机无法理解，它需要比较大小。

为此，我们需要将其转换为整数。使用int()功能。这里：

#convert it to an integer straight away
total = int(raw_input('What is the total amount for your online shopping?')) 
country = raw_input('Shipping within the US or Canada?')

if country == "US":
    if total <= 50:
        print "Shipping Costs $6.00"
    elif total <= 100:
            print "Shipping Costs $9.00"
    elif total <= 150:
            print "Shipping Costs $12.00"
    else:
        print "FREE"

if country == "Canada":
    if total <= 50:
        print "Shipping Costs $8.00"
    elif total <= 100:
        print "Shipping Costs $12.00"
    elif total <= 150:
        print "Shipping Costs $15.00"
    else:
        print "FREE"

希望这有帮助！

Answer 4

比较字符串时，它按字典顺序排列，就像在电话簿中一样。例如：

"a" < "b"：是的 "bill" < "bob"：是的 "100" < "3"：是的

如果要按照我们计算的顺序比较数字，则需要使用int类型。

total = int(raw_input('What is the total amount for your online shopping?'))

然后将代码中的所有字符串文字（如"50"）更改为50等整数文字。

Answer 5

此：

total = raw_input('What is the total amount for your online shopping?')

生成一个字符串。字符串和数字之间的比较定义不明确。您需要先将总数转换为数字。例如：

total = int(raw_input('What is the total amount for your online shopping?'))

（这会忽略输入错误处理，例如当用户的输入不是数字时）

请注意，Python 2.x和Python 3.x中的行为发生了变化。在Python 2.x：

不同类型的对象，除了不同的数字类型和不同的字符串类型，从不比较相等;这些对象是一致但任意排序的（因此排序异构数组会产生一致的结果）。

...

CPython实现细节：除了数字之外的不同类型的对象按其类型名称排序;不支持正确比较的相同类型的对象按其地址排序。

在Python 3.x中

：

不同类型的对象（不同的数字类型除外）从不相等。

Answer 6

使用raw_input时，您的用户输入以字符串形式出现，您无法以字符串格式计算数字。因此，您需要将字符串输入更改为整数才能进行比较。你可以这样做：

total = int(raw_input('What is the total amount for your online shopping?'))
country = raw_input('Shipping within the US or Canada?')

if country == "US":
    if total <= 50:
        print "Shipping Costs $6.00"
    elif total <= 100:
        print "Shipping Costs $9.00"
    elif total <= 150:
        print "Shipping Costs $12.00"
else:
    print "FREE"

elif country == "Canada":
    if total <= 50:
        print "Shipping Costs $8.00"
    elif total <= 100:
        print "Shipping Costs $12.00"
    elif total <= 150:
        print "Shipping Costs $15.00"
    else:
        print "FREE"

else:
    print "Try Again"

Answer 7

这就像添加苹果＆amp;房子得到的总数是不可能的。它必须是相同的类型，在这种情况下是整数类型，以获得总数。使用int（）将字符串转换为整数。

 total = int(raw_input('What is the total amount for your online shopping?'))

也可能（但不太可取）：

 total = raw_input('What is the total amount for your online shopping?')
 total = int(total)

Answer 8

输入返回字符串

如果应该合计返回用于数学运算的输入，则应浮动输入

总计=（raw_input（'您的网上购物总金额是多少？'）总计=浮动（总计）

Answer 9

删除 if 语句中整数的引号，例如：

if total <= "50" -------> if total <= 50

Answer 10

我在这里只是一个更新鲜和python编程。我试图解决你的问题。希望，这个可以帮到你。

if country == 'US':
if total <= 50:
    print ('Shipping Costs $6.00')
elif total <= 100:
        print ('Shipping Costs $9.00')
elif total <= 150:
        print ('Shipping Costs $12.00')
else:
    print ('FREE')

elif country == 'Canada':
if total <= 50:
    print ('Shipping Costs $8.00')
elif total <= 100:
    print ('Shipping Costs $12.00')
elif total <= 150:
    print ('Shipping Costs $15.00')
else:
    print ('FREE')

else:
print ('Country name is case sensetive so do it perfectly')

python if elif else声明

10 个答案: