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Determining complexity for recursive functions (Big O notation)
...nd I need help determining the complexity of these recursive functions. I know how to solve simple cases, but I am still trying to learn how to solve these harder cases. These were just a few of the example problems that I could not figure out. Any help would be much appreciated and would greatly he...
Get current date in milliseconds
...d it'll result in a negative value.
For example, if I run that code right now, it'll result in
currentTime = 1357234941
and
currentTime /seconds / minutes / hours / days = years
1357234941 / 60 / 60 / 24 / 365 = 43.037637652207
...
What's the difference between passing by reference vs. passing by value?
...by value vs. pass by reference" distinction as defined in the CS theory is now obsolete because the technique originally defined as "pass by reference" has since fallen out of favor and is seldom used now.1
Newer languages2 tend to use a different (but similar) pair of techniques to achieve the sam...
How to create a GUID/UUID using iOS
...ns the Unique ID of your iPhone.
EDIT: -[UIDevice uniqueIdentifier] is now deprecated and apps are being rejected from the App Store for using it. The method below is now the preferred approach.
If you need to create several UUID, just use this method (with ARC):
+ (NSString *)GetUUID
{
CFU...
Const in JavaScript: when to use it and is it necessary?
...eginning of 2014 and a lot has changed since then. ecmascript-6 support is now the norm. All modern browsers now support const so it should be pretty safe to use without any problems.
Original Answer from 2014
Despite having fairly decent browser support, I'd avoid using it for now. From MDN's a...
position: fixed doesn't work on iPad and iPhone
I have been struggling with fixed positioning in iPad for a while. I know iScroll and it does not always seem to work (even in their demo). I also know that Sencha has a fix for that, but I couldn't Ctrl + F the source code for that fix.
...
How can I determine what font a browser is actually using to render some text?
...
Per Wilfred Hughes' answer, Firefox now supports this natively. This article has more details.
This answer original referenced the "Font Finder" plugin, but only because it was from 4 years ago. The fact that old answers linger like this and the community can...
NodeJS / Express: what is “app.use”?
...t has a middleware stack that can be customized in app.configure()(this is now deprecated in version 4.x).
To setup your middleware, you can invoke app.use(<specific_middleware_layer_here>) for every middleware layer that you want to add (it can be generic to all paths, or triggered only on ...
Unique Constraint in Entity Framework Code First
...d compliant you should absolutely be able to enforce uniqueness this way. Now whether EF allows you to properly manage the transaction lifecycle this way is another question.
– mattmc3
May 1 '11 at 0:21
...
how to emulate “insert ignore” and “on duplicate key update” (sql merge) with postgresql?
...rows and with mysql i can do this with only ONE query without any looping. Now I wonder if this is possible with postgresql too: to use just one query to bulk update OR insert. You say: "you're best of splitting it into two queries, one for INSERT and one for UPDATE" but how can I do an insert which...