问题

I have translated the code-related part for you:

str1 = "许可证 123456"
str2 = "地址 123456"
str3 = "许可证号码 1234567"
str4 = "许可证号 1234"

我尝试匹配所有包含```许可证```、```地址```、```许可证号码```、```许可证号```之一，后跟精确6位数字的字符串。

我尝试了这个正则表达式： 
```python
re.search(r"(许可证|地址|许可证号码|许可证号)\d{6}$", str)

从我的理解来看，它应该匹配我的条件，但显然也匹配了超过6位数字的字符串（它不匹配少于6位数字的字符串）。

我该如何修正我的正则表达式？

<details>
<summary>英文:</summary>

Let say I have those 4 strings:

str1 = "license 123456"
str2 = "address 123456"
str3 = "license number 1234567"
str4 = "license num 1234"

I'm trying to match all the strings that have either ```"permit"|"license"|"license number"|license num"``` followed by exactly 6 digits.

I've tried this expression : 

re.search(r"(permit|license|license number|license num)\d{6}$", str)

From what I understood, it was suppose to match my criteria, but it apparently also matches string with more than 6 digits (it doesn't match strings with less than 6). 

How could I fix my regex expression ?   

</details>


# 答案1
**得分**: 1

我认为这可能有效：

    ^(permit|license|license number|license num)\s\d{6}$

或者这个，取决于你的搜索方式：

    \b(permit|license|license number|license num)\s\d{6}\b

<details>
<summary>英文:</summary>

I think this may work:

    ^(permit|license|license number|license num)\s\d{6}$

or this, depends on how you search:

    \b(permit|license|license number|license num)\s\d{6}\b

</details>



# 答案2
**得分**: 1

Here's the translated code:

首先，“license”|“license number”|“license num”是逻辑上的冗余，可以缩减为“license”本身。

其次，您没有指定可以出现在我们的许可证和数字之间的字符模式。这可以通过 .* 完成，所以主要模式变成了“permit|license.*[0-9]{6}$”。

因此，最终的代码如下：

```python
str1 = "license 123456"
str2 = "address 123456"
str3 = "license number 1234567"
str4 = "license num 1234"
str_lst=[str1,str2,str3,str4]
import re
for i in str_lst:
    try:
        print(re.search("(permit|license)[^0-9]*[0-9]{6}$", i).string)
    except AttributeError:
        print('not matching')

str1 = "license 123456"
str2 = "address 123456"
str3 = "license number 1234567"
str4 = "license num 1234"
str_lst=[str1,str2,str3,str4]
import re
for i in str_lst:
    try:
        print(re.search("(permit|license)[^0-9]*[0-9]{6}$", i).string)
    except AttributeError :
        print('not matching')