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How to get first and last day of previous month (with timestamp) in SQL Server
...SQL does.
– daOnlyBG
May 22 '17 at 15:14
Datediff only takes two arguments. I get #1582 - Incorrect parameter count in...
C++并发编程（中文版） - 文档下载 - 清泛网 - 专注C/C++及内核技术
...3
1.2 为什么使用并发… 4
1.2.1 因划分重点而使用并发… 5
1.2.2 为了提高性能而使用并发… 5
1.2.3 什么时候不使用并发… 6
1.3 在C++中使用并发和多线程… 7
1.3.1 多线程在C++中的发展历程… 7
1.3.2 新标准对于并发的支持… 8
1.3...
What is the optimal Jewish toenail cutting algorithm?
...ish rule. Luckily, humans only have five toes per foot*, so there are only 5! = 120 unrestricted sequences.
Python example:
#seq is only valid when consecutive elements in the list differ by at least two.
def isValid(seq):
for i in range(len(seq)-1):
a = seq[i]
b = seq[i+1]
...
Counting the occurrences / frequency of array elements
...|
edited Jan 10 '19 at 22:56
jpaugh
5,44044 gold badges3232 silver badges7979 bronze badges
answered Apr...
How to get thread id from a thread pool?
I have a fixed thread pool that I submit tasks to (limited to 5 threads). How can I find out which one of those 5 threads executes my task (something like "thread #3 of 5 is doing this task")?
...
Expand a random range from 1–5 to 1–7
Given a function which produces a random integer in the range 1 to 5, write a function which produces a random integer in the range 1 to 7.
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Maximum number of characters using keystrokes A, Ctrl+A, Ctrl+C and Ctrl+V
...y have to consider up to 4 consecutive pastes, since select, copy, paste x 5 is equivalent to select, copy, paste, select, copy, paste and the latter is better since it leaves us with more in the clipboard. Once we've reached n, we have the desired result.
The complexity might appear to be O(N), bu...
How can I list (ls) the 5 last modified files in a directory?
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5 Answers
5
Active
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All combinations of a list of lists
...tools.product:
>>> import itertools
>>> a = [[1,2,3],[4,5,6],[7,8,9,10]]
>>> list(itertools.product(*a))
[(1, 4, 7), (1, 4, 8), (1, 4, 9), (1, 4, 10), (1, 5, 7), (1, 5, 8), (1, 5, 9), (1, 5, 10), (1, 6, 7), (1, 6, 8), (1, 6, 9), (1, 6, 10), (2, 4, 7), (2, 4, 8), (2, 4, 9)...
How to get last N records with activerecord?
...t N records simply by using last method:
Record.last(N)
Example:
User.last(5)
Returns 5 users in descending order by their id.
Deprecated (Old Answer)
An active record query like this I think would get you what you want ('Something' is the model name):
Something.find(:all, :order => "id desc", :l...