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What is the difference between Strategy design pattern and State design pattern?
...
Honestly, the two patterns are pretty similar in practice, and the defining difference between them tends to vary depending on who you ask. Some popular choices are:
States store a reference to the context object that contai...
Convert base class to derived class [duplicate]
Is it possible in C# to explicitly convert a base class object to one of it's derived classes? Currently thinking I have to create a constructor for my derived classes that accept a base class object as a parameter and copy over the property values. I don't really like this idea, so I'd like to avoi...
Is it better to use std::memcpy() or std::copy() in terms to performance?
...owever, after my first few attempts, I got results that varied wildly from one run to the next, so I'm guessing there was some sort of OS activity going on. I decided to start over.
Same compiler settings and flags. There is only one version of MD5, and it's faster than SHA-2, so I did 3000 loops o...
How do I base64 encode (decode) in C?
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Here's the one I'm using:
#include <stdint.h>
#include <stdlib.h>
static char encoding_table[] = {'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H',
'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P',
...
What is the best collation to use for MySQL with PHP? [closed]
...en comparing characters in the language) and performance. The only special one is utf8_bin which is for comparing characters in binary format.
utf8_general_ci is somewhat faster than utf8_unicode_ci, but less accurate (for sorting). The specific language utf8 encoding (such as utf8_swedish_ci) cont...
What is the difference between “ is None ” and “ ==None ”
...ison any way it chooses, and it
can choose to make comparison against
None mean something (which actually
makes sense; if someone told you to
implement the None object from
scratch, how else would you get it to
compare True against itself?).
Practically-speaking, there is not much diff...
uint8_t vs unsigned char
...imply a character, whereas in the context of a UTF8 string, it may be just one byte of a multibyte character. Using uint8_t could make it clear that one shouldn't expect a character at every position -- in other words that each element of the string/array is an arbitrary integer that one shouldn't m...
Monad in plain English? (For the OOP programmer with no FP background)
...on the amplified type, that obeys the rules of functional composition mentioned before.
There is often a way to get the unamplified type back out of the amplified type. Strictly speaking this operation is not required to have a monad. (Though it is necessary if you want to have a comonad. We won't c...
What are the differences between a multidimensional array and an array of arrays in C#?
...wer below, It might be the case that on windows jagged arrays are fast but one has to realize that this is entirely CLR specific and not the case with e.g. mono...
– John Leidegren
Mar 1 '09 at 8:09
...
How to concatenate text from multiple rows into a single text string in SQL server?
... answer.
I had a similar issue when I was trying to join two tables with one-to-many relationships. In SQL 2005 I found that XML PATH method can handle the concatenation of the rows very easily.
If there is a table called STUDENTS
SubjectID StudentName
---------- -------------
1 ...