如何以这种方式按字母顺序排列？

Question

我必须对用户输入的名称进行排序，而不使用列表排序方法。到目前为止，这就是我所拥有的，但在定义“一”、“二”和“三”时，我遇到了问题。我需要程序通过每一个字母，以确保它是真正的字母。有人能帮忙吗？

name1=str(input("Enter name #1: "))
name2=str(input("Enter name #2: "))
name3=str(input("Enter name #3: "))

one = name1[0].upper() + name1[1].upper() + name1[2].upper()
two = name2[0].upper() + name2[1].upper() + name2[2].upper()
three = name3[0].upper() + name3[1].upper() + name3[2].upper()

if one < two and two < three:
     print("These names in alphabetical order are: ", name1, name2, name3)
elif one < two and three < two:
     print("These names in alphabetical order are: ", name1, name3, name2)     
elif two < three and three < one:
     print("These names in alphabetical order are: ", name2, name3, name1)
elif two < one and one < three:
     print("These names in alphabetical order are: ", name2, name1, name3)
elif three < two and two < one:
     print("These names in alphabetical order are: ", name3, name2, name1)
else:
     print("These names in alphabetical order are: ", name3, name1, name2)

提前谢谢！编辑我的问题是在定义‘1’2‘’和‘3’，它需要运行所有的字母在输入。现在，它贯穿前三个字母，但如果我添加下一个字母，并且只给出三个字母的名称，则会出现错误。如果我使用len函数，它会告诉我它是一个整数

Answer 1

我需要程序通过每一个字母，以确保它是真正的字母。

这就是字符串比较所做的。代码的问题是将one、two和three限制在输入字符串的前三个字母上。相反，您应该大写整个名称并比较它们。

name1 = input("Enter name #1: ")  # no need for str(...)
... # same for name2, name3

one = name1.upper()  # uppercase whole nam, not just first three letters
... # same for two, three

answer = "These names in alphabetical order are: "  # don't repeat this X times
if one < two < three:  # comparison chaining
    print(answer, name1, name2, name3)
elif one < three < two:
    print(answer, name1, name3, name2)
elif ...:
    # a whole bunch more
else:
    print(answer, name3, name2, name1)

Answer 2

您可以使用好的旧排序算法。

letters = [name1.upper(),name2.upper(),name3.upper()] 
for i in range(len(letters)):
   for j in range(i,len(letters)):
             if letters[i] > letters[j]:
                     letters[i],letters[j] = letters[j],letters[i]