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How do malloc() and free() work?
I want to know how malloc and free work.
13 Answers
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Why do we use __init__ in Python classes?
...Spot is a bit of a cripple and is mostly yellow. The __init__ function is called a constructor, or initializer, and is automatically called when you create a new instance of a class. Within that function, the newly created object is assigned to the parameter self. The notation self.legs is an attrib...
What does O(log n) mean exactly?
...g that the size of the input affects the growth of the algorithm proportionally...and the same goes for, for example, quadratic time O(n2) etc..even algorithms, such as permutation generators, with O(n!) times, that grow by factorials.
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When is it right for a constructor to throw an exception?
...nstructor's job is to bring the object into a usable state. There are basically two schools of thought on this.
One group favors two-stage construction. The constructor merely brings the object into a sleeper state in which it refuses to do any work. There's an additional function that does the act...
Expand a div to fill the remaining width
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The solution to this is actually very easy, but not at all obvious. You have to trigger something called a "block formatting context" (BFC), which interacts with floats in a specific way.
Just take that second div, remove the float, and give it overfl...
How can I make the cursor turn to the wait cursor?
... it takes a little while to do. How can I display the Wait/Busy Cursor (usually the hourglass) to the user to let them know the program is doing something?
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Count(*) vs Count(1) - SQL Server
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There is no difference.
Reason:
Books on-line says "COUNT ( { [ [ ALL | DISTINCT ] expression ] | * } )"
"1" is a non-null expression: so it's the same as COUNT(*).
The optimizer recognizes it for what it is: trivial.
The same as EXISTS (SELECT * ... or EXISTS (SELECT 1 ...
Example:
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Undoing a git rebase
...uble check this, though as I haven't verified this recently.
Per default, all reflogs are activated for non-bare repositories:
[core]
logAllRefUpdates = true
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How do you read CSS rule values with JavaScript?
I would like to return a string with all of the contents of a CSS rule, like the format you'd see in an inline style. I'd like to be able to do this without knowing what is contained in a particular rule, so I can't just pull them out by style name (like .style.width etc.)
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On Duplicate Key Update same as insert
...real life query there are differences. My question is quiet simple: Do I really need to specify all the fields (and values in my first example) if they are the same as in the insert? I just want to insert all or if there is a unique value match: update all.
– Roy
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