大约有 48,000 项符合查询结果（耗时：0.0639秒） [XML]
Quicksort: Choosing the pivot
...
Choosing a random pivot minimizes the chance that you will encounter worst-case O(n2) performance (always choosing first or last would cause worst-case performance for nearly-sorted or nearly-reverse-sorted data). Choosing the middle el...
What is the most efficient/elegant way to parse a flat table into a tree?
..., we can say that all popular SQL databases support recursive queries in standard syntax.
WITH RECURSIVE MyTree AS (
SELECT * FROM MyTable WHERE ParentId IS NULL
UNION ALL
SELECT m.* FROM MyTABLE AS m JOIN MyTree AS t ON m.ParentId = t.Id
)
SELECT * FROM MyTree;
I tested recursive que...
When would anyone use a union? Is it a remnant from the C-only days?
...pace to work with, or when you're developing an API (or something similar) and you want to force the end user to have only one instance of several objects/types at one time. Are these two guesses even close to right?
...
Is gcc 4.8 or earlier buggy about regular expressions?
...
<regex> was implemented and released in GCC 4.9.0.
In your (older) version of GCC, it is not implemented.
That prototype <regex> code was added when all of GCC's C++0x support was highly experimental, tracking early C++0x drafts and being ma...
What is the difference between quiet NaN and signaling NaN?
I have read about floating-point and I understand that NaN could result from operations. But I can't understand what these are concepts exactly. What is the difference between them?
...
What is a build tool?
For past 4 years, I have been programming with Eclipse (for Java), and Visual Studio Express (for C#). The IDEs mentioned always seemed to provide every facility a programmer might ask for (related to programming, of course).
...
When do I really need to use atomic instead of bool? [duplicate]
...ic by nature" unless it is an std::atomic*-something. That's because the standard says so.
In practice, the actual hardware instructions that are emitted to manipulate an std::atomic<bool> may (or may not) be the same as those for an ordinary bool, but being atomic is a larger concept with wi...
Open file via SSH and Sudo with Emacs
...stion|ssh:you@remotehost:/path RET
Which connects firstly as bird@bastion, and from there to you@remotehost:/path
/su: or /sudo: on remote hosts
You can also use this syntax to sudo/su to root (or of course any other user) on a remote host:
C-xC-f /ssh:you@remotehost|sudo:remotehost:/path/to/file RE...
Overwrite or override
It might seem to be a stupid question but I'm just so curious and want to use the correct term when talking about the issue. Couldn't find a similar question here so I decided to create a new one.
...
Run an untrusted C program in a sandbox in Linux that prevents it from opening files, forking, etc.?
...was wondering if there exists a way to run an untrusted C program under a sandbox in Linux. Something that would prevent the program from opening files, or network connections, or forking, exec, etc?
...