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Difference between Covariance & Contra-variance
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The question is "what is the difference between covariance and contravariance?"
Covariance and contravariance are properties of a mapping function that associates one member of a set with another. More specifically, a mapping can be cova...
When is a language considered a scripting language? [closed]
...tead of compiled". That would make PHP (for example) a scripting language. Is that the only criterion? Or are there other criteria?
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What is Normalisation (or Normalization)?
Why do database guys go on about normalisation?
10 Answers
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What is the difference between -viewWillAppear: and -viewDidAppear:?
What is the difference between -[UIViewController viewWillAppear:] and -[UIViewController viewDidAppear:] ?
12 Answers
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Undefined behavior and sequence points
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C++98 and C++03
This answer is for the older versions of the C++ standard. The C++11 and C++14 versions of the standard do not formally contain 'sequence points'; operations are 'sequenced before' or 'unsequenced' or 'indeterminately sequence...
How to find time complexity of an algorithm
...size of its input, and then simplify the expression to the largest (when N is very large) term and can include any simplifying constant factor.
For example, lets see how we simplify 2N + 2 machine instructions to describe this as just O(N).
Why do we remove the two 2s ?
We are interested in the ...
What exactly is a reentrant function?
Most of the times , the definition of reentrance is quoted from Wikipedia :
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if A vs if A is not None:
...; should return False or True, or their integer equivalents 0 or 1. When this method is not defined, __len__() is called, if it is defined, and the object is considered true if its result is nonzero. If a class defines neither __len__() nor __nonzero__(), all its instances are considered true.
On ...
What is the default initialization of an array in Java?
...thing in a Java program not explicitly set to something by the programmer, is initialized to a zero value.
For references (anything that holds an object) that is null.
For int/short/byte/long that is a 0.
For float/double that is a 0.0
For booleans that is a false.
For char that is the null char...
What are the advantages of using nullptr?
This piece of code conceptually does the same thing for the three pointers (safe pointer initialization):
7 Answers
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