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What is recursion and when should I use it?
...ily be replaced by more efficient iteration. After all, recursion suffers from function call overhead, which in the example above could be substantial compared to the operation inside the function itself.
So the whole reason to do recursion rather than iteration should be to take advantage of the ...
How do I ignore a directory with SVN?
... 'cache' dir still will be listed in 'svn st'. Is there a way to remove it from the view? (without delete from the disk)
– Tom Brito
Aug 1 '16 at 20:45
add a comment
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How do I apply the for-each loop to every character in a String?
...to generate the char[] (which is mutable), so there is some cost penalty.
From the documentation:
[toCharArray() returns] a newly allocated character array whose length is the length of this string and whose contents are initialized to contain the character sequence represented by this string.
...
Pros and cons of AppSettings vs applicationSettings (.NET app.config / Web.config)
...have them type-safe
and checked
b) You can cleanly separate YOUR settings from everyone
else's. And you can reuse your config code, too!
There's a series of really good articles on you to demystify the .NET 2.0 configuration system on CodeProject:
Unraveling the mysteries of .NET 2.0 configurat...
Validating email addresses using jQuery and regex
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thanks aSeptik apart from "missing" the e from mailaddress works well yes know that no regex 100% exists, but can get "pretty" close
– RussP
May 19 '10 at 7:46
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How to prevent Browser cache for php site
...ricer (a Linux distro known for "going fast" by being excessively compiled from source and architecture-tuned) I'd clock a stat call. Without filesystem cache, 16ns, tops? With cache, reliably < 8ns. Nanoseconds. And on my system MD5 can process 754 MiB/s without blinking. (openssl speed md5...
count (non-blank) lines-of-code in bash
...
Just habit. I read pipelines from left to right, which means I usually start with cat, then action, action, action, etc. Clearly, the end result is the same.
– Michael Cramer
Sep 24 '08 at 14:06
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What's better to use in PHP, $array[] = $value or array_push($array, $value)?
...ptimisations like these are rarely worth the effort. If you are writing it from scratch, do it how makes most sense, and only then, if it's a little slow to produce a page, profile it. The chances of getting all the way down to having to change something like this to speed things up is slight.
...
How do I schedule jobs in Jenkins?
...For the past few versions (2014), Jenkins have a new parameter, H (extract from the Jenkins code documentation):
To allow periodically scheduled tasks to produce even load on the system, the symbol H (for “hash”) should be used wherever possible.
For example, using 0 0 * * * for a dozen daily j...
Relative frequencies / proportions with dplyr
...2 0 4 4 0.2105263
# 3 1 4 8 0.6153846
# 4 1 5 5 0.3846154
From the dplyr vignette:
When you group by multiple variables, each summary peels off one level of the grouping. That makes it easy to progressively roll-up a dataset.
Thus, after the summarise, the last grouping variab...