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Count the occurrences of DISTINCT values
...as an aggregate function works on the entire dataset, suming, counting, or concating the specified field down to one row. Group by subdivides the dataset into chunks based on unique combos of the specified fields
– Avatar_Squadron
Aug 24 '12 at 16:37
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Any reason not to use '+' to concatenate two strings?
A common antipattern in Python is to concatenate a sequence of strings using + in a loop. This is bad because the Python interpreter has to create a new string object for each iteration, and it ends up taking quadratic time. (Recent versions of CPython can apparently optimize this in some cases, b...
How to reference generic classes and methods in xml documentation
.... (This is seen e.g. on the MSDN refence page for the static System.String.Concat(IEnumerable<string>) method). :
XML documentation comment cref rules:
Surround the generic type parameter list with curly braces {} instead of with <> angle brackets. This spares you from escaping the la...
How to generate gcc debug symbol outside the build target?
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Refer @Lance Richardson answer comments for an example.
– GuruM
Jul 19 '13 at 11:02
7
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How do I remove code duplication between similar const and non-const member functions?
...780321334879.
Here's Meyers' solution (simplified):
struct C {
const char & get() const {
return c;
}
char & get() {
return const_cast<char &>(static_cast<const C &>(*this).get());
}
char c;
};
The two casts and function call may be ugly but it's c...
Divide a number by 3 without using *, /, +, -, % operators
...* fp=fopen("temp.dat","w+b");
int number=12346;
int divisor=3;
char * buf = calloc(number,1);
fwrite(buf,number,1,fp);
rewind(fp);
int result=fread(buf,divisor,number,fp);
printf("%d / %d = %d", number, divisor, result);
free(buf);
fclose(fp);
return 0;
}
If...
Get last element of Stream/List in a one-liner
...akes a point, further the API documentation states that reduce("", String::concat) is an inefficient but correct solution for string concatenation, which implies maintenance of the encounter order.The intention is well-known,the documentation has to catch up.
– Holger
...
Useful GCC flags for C
...the required alignment of the target is increased. For example, warn if a char * is cast to an int * on machines where integers can only be accessed at two- or four-byte boundaries.
-Wstrict-prototypes: warn if a function is declared or defined without specifying the argument types.
-Wstrict-overfl...
Linux command (like cat) to read a specified quantity of characters
...ere a command like cat in linux which can return a specified quantity of characters from a file?
9 Answers
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What are “connecting characters” in Java identifiers?
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Here is a list of connecting characters. These are characters used to connect words.
http://www.fileformat.info/info/unicode/category/Pc/list.htm
U+005F _ LOW LINE
U+203F ‿ UNDERTIE
U+2040 ⁀ CHARACTER TIE
U+2054 ⁔ INVERTED UNDERTIE
U+FE33 ︳ PRE...