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How does Python's super() work with multiple inheritance?
I'm pretty much new in Python object oriented programming and I have trouble
understanding the super() function (new style classes) especially when it comes to multiple inheritance.
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Why do we check up to the square root of a prime number to determine if it is prime?
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If a number n is not a prime, it can be factored into two factors a and b:
n = a * b
Now a and b can't be both greater than the square root of n, since then the product a * b would be greater than sqrt(n) * sqrt(n) = n. So in any factorization of n, at least one of the factors must be smal...
public friend swap member function
In the beautiful answer to the copy-and-swap-idiom there is a piece of code I need a bit of help:
2 Answers
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Xcode/Simulator: How to run older iOS version?
...s in your binary you will not be able to run it on anything before iOS 4.0 and it will be rejected if you try and submit a binary like this.
You can still run the simulator from 3.2 onwards after upgrading.
In the iPhone Simulator try selecting Hardware -> Version -> 3.2
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Spinlock versus Semaphore
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Spinlock and semaphore differ mainly in four things:
1. What they are
A spinlock is one possible implementation of a lock, namely one that is implemented by busy waiting ("spinning"). A semaphore is a generalization of a lock (or, th...
Drawing a connecting line between two elements [closed]
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jsPlumb is an option available that supports drag and drop, as seen by its numerous demos, including the Flowchart demo.
It is available in a free Community edition, and a paid Toolkit edition.
The Toolkit edition wraps the Community edition with a comprehensive data bi...
What's the syntax for mod in java
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Careful with the terms mod and modular because n (mod m) IS ALWAYS >= 0 but not n % m. n % m is in the range > -m and < m. Although Java has a remainder operator for int and long types, it has no modulus function or operator. I.e., -12 % 10 = ...
What are the rules for calling the superclass constructor?
...bar
}
};
More info on the constructor's initialization list here and here.
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MongoDB and “joins” [duplicate]
...ll only be evaluated when needed. A join (in a SQL database) on the other hand will resolve relationships and return them as if they were a single table (you "join two tables into one").
You can read more about DBRef here:
http://docs.mongodb.org/manual/applications/database-references/
There are ...
.keyCode vs. .which
... The answer below was written in 2010. Here many years later, both keyCode and which are deprecated in favor of key (for the logical key) and code (for the physical placement of the key). But note that IE doesn't support code, and its support for key is based on an older version of the spec so isn't...