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The best way to remove duplicate values from NSMutableArray in Objective-C?
...ded NSOrderedSet to iOS 5 and Mac OS X 10.7. What had been an algorithm is now two lines of code:
NSOrderedSet *orderedSet = [NSOrderedSet orderedSetWithArray:yourArray];
NSArray *arrayWithoutDuplicates = [orderedSet array];
If you are worried about the order and you're running on iOS 4 or earl...
Select N random elements from a List in C#
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@recursive: The proof is almost trivial. We know how to select K items out of K for any K and how to select 0 items out of N for any N. Assume we know a method to uniformly select K or K-1 items out of N-1 >= K; then we can select K items out of N by selecting the fi...
How to detect if multiple keys are pressed at once using JavaScript?
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Note: keyCode is now deprecated.
Multiple keystroke detection is easy if you understand the concept
The way I do it is like this:
var map = {}; // You could also use an array
onkeydown = onkeyup = function(e){
e = e || event; // to deal w...
EC2 Can't resize volume after increasing size
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This answer is now deprecated now that AWS supports online resizing for EBS volumes.
– Dale Anderson
Jul 6 '17 at 17:49
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How can I do width = 100% - 100px in CSS?
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Modern browsers now support the:
width: calc(100% - 100px);
To see the list of supported browser versions checkout: Can I use calc() as CSS unit value?
There is a jQuery fallback: css width: calc(100% -100px); alternative using jquery
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SPAN vs DIV (inline-block)
...pec, <span> is an inline element and <div> is a block element. Now that can be changed using the display CSS property but there is one issue: in terms of HTML validation, you can't put block elements inside inline elements so:
<p>...<div>foo</div>...</p>
is not...
Clustered vs Non-Clustered
My lower level knowledge of SQL (Server 2008) is limited, and is now being challanged by our DBAs. Let me explain (I have mentioned obvious statements in the hope that I am right, but if you see something wrong, please tell me) the scenario:
...
Rails DB Migration - How To Drop a Table?
I added a table that I thought I was going to need, but now no longer plan on using it. How should I remove that table?
22 ...
MySQL: Transactions vs Locking Tables
...posit all the service fees charged on the transaction. Given (as everyone knows these days) that banks are extraordinarily stupid, let's say their system works like this:
$balance = "GET BALANCE FROM your ACCOUNT";
if ($balance < $amount_being_paid) {
charge_huge_overdraft_fees();
}
$balance...
Make Vim show ALL white spaces as a character
...l, in combination with
:set listchars=...
display invisible characters.
Now, there isn't an explicit option which you can use to show whitespace, but in listchars, you could set a character to show for everything BUT whitespace. For example, mine looks like this
:set listchars=eol:$,tab:>-,tr...