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Simple regular expression for a decimal with a precision of 2
...t:
\d+(\.\d{1,2})?
Both assume that both have at least one digit before and one after the decimal place.
To require that the whole string is a number of this form, wrap the expression in start and end tags such as (in Perl's form):
^\d+(\.\d{1,2})?$
To match numbers without a leading digit be...
How to add a right button to a UINavigationController?
...ll might be quite a while before it displays, no point in doing work early and tying up memory.
- (void)viewDidLoad {
[super viewDidLoad];
UIBarButtonItem *anotherButton = [[UIBarButtonItem alloc] initWithTitle:@"Show" style:UIBarButtonItemStylePlain target:self action:@selector(refreshPropert...
C++, What does the colon after a constructor mean? [duplicate]
...e the body of the constructor executes.
For case #1, I assume you understand inheritance (if that's not the case, let me know in the comments). So you are simply calling the constructor of your base class.
For case #2, the question may be asked: "Why not just initialise it in the body of the cons...
Purge or recreate a Ruby on Rails database
...ave a dev Ruby on Rails database full of data. I want to delete everything and rebuild the database. I'm thinking of using something like:
...
Scoping in Python 'for' loops
I'm not asking about Python's scoping rules; I understand generally how scoping works in Python for loops. My question is why the design decisions were made in this way. For example (no pun intended):
...
How do I implement an Objective-C singleton that is compatible with ARC?
How do I convert (or create) a singleton class that compiles and behaves correctly when using automatic reference counting (ARC) in Xcode 4.2?
...
How do we count rows using older versions of Hibernate (~2009)?
... answered Sep 3 '09 at 10:34
SalandurSalandur
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How to dynamically change a web page's title?
...
Update: as per the comments and reference on SearchEngineLand
most web crawlers will index the updated title. Below answer is obsolete, but the code is still applicable.
You can just do something like, document.title = "This is the new
page title...
How to prove that a problem is NP complete?
...least one vertex in the cover set?) is in NP:
our input X is some graph G and some number k (this is from the problem definition)
Take our information C to be "any possible subset of vertices in graph G of size k"
Then we can write an algorithm V that, given G, k and C, will return whether that s...
while (1) Vs. for (;;) Is there a speed difference?
...ase, but chances are the code inside of the loop is going to be a few thousand times more expensive than the loop itself anyway, so who cares?
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