题目描述:
Remove all elements from a linked list of integers that have value val.
Example
Given: 1 --> 2 --> 6 --> 3 --> 4 --> 5 --> 6, val = 6
Return: 1 --> 2 --> 3 --> 4 ...
最后更新于 .
Remove all elements from a linked list of integers that have value val.
Example
Given: 1 --> 2 --> 6 --> 3 --> 4 --> 5 --> 6, val = 6
Return: 1 --> 2 --> 3 --> 4 ...
最后更新于 .
Write an algorithm to determine if a number is "happy".
A happy number is a number defined by the following process: Starting with any positive integer, replace the number by the sum of the squares of its digits, and ...
最后更新于 .
一个搭建在SAE上的Django应用,使用新浪微博提供的Python SDK已经稳定运行一年有余,但最近开始持续出现微博认证失败的状况。
摘录微博Python SDK的错误提示如下所示:
ERROR:django.request:Internal Server Error: /weibo/auth/
Traceback (most recent call last):
File "/usr/local/sae/python/3rd/django-1.5/django/core/handlers/base.py", line 115, in get_response
response = callback(request, *callback_args, **callback_kwargs)
File "/data1/www/htdocs/838/app/1/mysite/views.py", line 42, in auth
res = weibo_util.keep_user(code,api,redirect_uri)
File "/data1/www/htdocs/838/app/1/util/weibo_util.py", line 86, in keep_user
r ...
最后更新于 .
在Django ORM中,使用order_by()方法对包含关联关系的模型进行排序时,返回结果中可能会出现重复元素。
假设有下面的两个模型Client和Interaction,Client为顾客,Interaction为交互。
Client类中包含顾客的姓名和联系方式,Interaction类中包含标题、时间、待办事项、截止日期。
class Client(models.Model):
name = models.CharField(max_length=255, unique=True)
contact = models.CharField(max_length=255, null=True, blank=True)
class Interaction(models.Model):
client = models.ForeignKey(Client)
title = models.TextField()
when = models.DateTimeField()
todo = models.TextField(null=True, blank=True)
deadline = models.DateTimeField(null=True, blank=True)
现在想要查询按照交互的截止日期倒序排列的客户列表。
'clients' : Client.objects.all().order_by('-interaction__deadline'),
返回结果中包含重复元素。由于Client和Interaction为一对多的关系,因此对于每一个Interaction都返回了一个Client元素,而非仅仅是对结果进行排序。大家提到需要使用distinct(),但是distinct()对于这个特例并不适用,因为考虑到它们彼此之间存在的关联关系,结果返回值已经唯一的了。
通过Google,我发现了解决方法!相关博文链接:http://archlinux.me/dusty/2010/12/07/django-dont-use-distinct-and-order_by-across-relations/ ...
最后更新于 .
Given a range [m, n] where 0 <= m <= n <= 2147483647, return the bitwise AND of all numbers in this range, inclusive.
For example, given the range [5, 7], you should return 4.
给定范围[m, n],其中 0 <= ...