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What does “O(1) access time” mean?
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You're going to want to read up on Order of complexity.
http://en.wikipedia.org/wiki/Big_O_notation
In short, O(1) means that it takes a constant time, like 14 nanoseconds, or three minutes no matter the amount of data in the set.
O(n) means it takes an amo...
What's better at freeing memory with PHP: unset() or $var = null
...ting to know if one is better than the other. I have been using unset() for most of my coding, but I've recently looked through a few respectable classes found off the net that use $var = null instead.
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Purpose of Trigraph sequences in C++?
According to C++'03 Standard 2.3/1:
9 Answers
9
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Android equivalent to NSNotificationCenter
In the process of porting an iPhone application over to android, I am looking for the best way to communicate within the app. Intents seem to be the way to go, is this the best (only) option? NSUserDefaults seems much lighter weight than Intents do in both performance and coding.
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What is mod_php?
While going through a Zend tutorial , I came across the following statement:
6 Answers
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How to find the Git commit that introduced a string in any branch?
...mmit in
any branch, how can I do that? I found something (that I modified for Win32),
but git whatchanged doesn't seem to be looking into the different branches
(ignore the py3k chunk, it's just a msys/win line feed fix)
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How do I check if an element is really visible with JavaScript? [duplicate]
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For the point 2.
I see that no one has suggested to use document.elementFromPoint(x,y), to me it is the fastest way to test if an element is nested or hidden by another. You can pass the offsets of the targetted element to th...
View.setPadding accepts only in px, is there anyway to setPadding in dp?
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Hi, I have a question. Is this formula used for only padding or anything else? e.g. margin or dimmension of a rectangle?
– emeraldhieu
Jul 9 '11 at 16:01
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MySQL Update Inner Join tables query
I have no idea what the problem is. Using MySQL 5.0 I get a compile error when attempting to run the following MySQL update query:
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How can I use pointers in Java?
...= new Tiger();
Tiger third;
Dereferencing a null:
first.growl(); // ERROR, first is null.
third.growl(); // ERROR, third has not been initialized.
Aliasing Problem:
third = new Tiger();
first = third;
Losing Cells:
second = third; // Possible ERROR. The old value of second is lost. ...