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Why can't I initialize non-const static member or static array in class?
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Why I can't initialize static data members in class?
The C++ standard allows only static constant integral or enumeration types to be initialized inside the class. This is the reason a is allowed to be initialized while others are not.
Reference:
C++03 9.4.2 Static data members
§4
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Fast permutation -> number -> permutation mapping algorithms
...you have n possibilities, so you can describe this with a number between 0 and n-1. For the position that the next element ends up at, you have n-1 remaining possibilities, so you can describe this with a number between 0 and n-2.
Et cetera until you have n numbers.
As an example for n = 5, consid...
Fastest way to list all primes below N
...t William Hanks for primesfrom2to, primesfrom3to, rwh_primes, rwh_primes1, and rwh_primes2.
Of the plain Python methods tested, with psyco, for n=1000000,
rwh_primes1 was the fastest tested.
+---------------------+-------+
| Method | ms |
+---------------------+-------+
| rwh_prime...
ObjectiveC Parse Integer from String
I'm trying to extract a string (which contains an integer) from an array and then use it as an int in a function. I'm trying to convert it to a int using intValue.
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How to convert from System.Enum to base integer?
...stem.Enum derived type to its corresponding integer value, without casting and preferably without parsing a string.
8 Answe...
App Inventor 2开发简单计算器 - App Inventor 2 中文网 - 清泛IT论坛，有思想、有深度
计算器这个看似简单的应用，当你一旦着手去制作时，就会发现写出来的程序漏洞百出，那些在人类看来理所当然的逻辑，对于计算机来说，却是浑然不知，一定要将每个细节都照顾到，程序才能如你所愿地运行，否则就会出现...
C# Ignore certificate errors?
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Add a certificate validation handler. Returning true will allow ignoring the validation error:
ServicePointManager
.ServerCertificateValidationCallback +=
(sender, cert, chain, sslPolicyErrors) => true;
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make an html svg object also a clickable link
I have an SVG object in my HTML page and am wrapping it in an anchor so when the svg image is clicked it takes the user to the anchor link.
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Why do we copy then move?
I saw code somewhere in which someone decided to copy an object and subsequently move it to a data member of a class. This left me in confusion in that I thought the whole point of moving was to avoid copying. Here is the example:
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Test if a vector contains a given element
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Both the match() (returns the first appearance) and %in% (returns a Boolean) functions are designed for this.
v <- c('a','b','c','e')
'b' %in% v
## returns TRUE
match('b',v)
## returns the first location of 'b', in this case: 2
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