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If strings are immutable in .NET, then why does Substring take O(n) time?
... typically use "substring" to extract a short string -- say, ten or twenty characters -- out of a somewhat longer string -- maybe a couple hundred characters. You have a line of text in a comma-separated file and you want to extract the third field, which is a last name. The line will be maybe a cou...
Best practices/performance: mixing StringBuilder.append with String.concat
...end(sN).toString();
concat()
String s = s1.concat(s2);
String creates char[] array that can fit both s1 and s2. Copies s1 and s2 contents to this new array. Actually requires less work then + operator.
StringBuilder.append()
Maintains an internal char[] array that grows when needed. No extra ...
How do I convert between big-endian and little-endian values in C++?
...nsigned __int64 _byteswap_uint64(unsigned __int64 value);
8 bit numbers (chars) don't need to be converted.
Also these are only defined for unsigned values they work for signed integers as well.
For floats and doubles it's more difficult as with plain integers as these may or not may be in the h...
What is a “surrogate pair” in Java?
...
The term "surrogate pair" refers to a means of encoding Unicode characters with high code-points in the UTF-16 encoding scheme.
In the Unicode character encoding, characters are mapped to values between 0x0 and 0x10FFFF.
Internally, Java uses the UTF-16 encoding scheme to store strings ...
In C# what is the difference between ToUpper() and ToUpperInvariant()?
...d to hear that there are various other capitalization issues around elided characters etc. This is just one example I know off the top of my head... partly because it bit me years ago in Java, where I was upper-casing a string and comparing it with "MAIL". That didn't work so well in Turkey...
...
How do I change bash history completion to complete what's already on the line?
...Readline library.
#
# Arrow keys in keypad mode
#
"\C-[OD" backward-char
"\C-[OC" forward-char
"\C-[OA" previous-history
"\C-[OB" next-history
#
# Arrow keys in ANSI mode
#
"\C-[[D" backward-char
"\C-[[C" forward-char
"\C-[[A" previous-history
"\C-[[B...
Uint8Array to string in Javascript
... string (I believe Javascript uses 16 bit Unicode)? I dont want to add one character at the time as the string concaternation would become to CPU intensive.
...
How to read a line from the console in C?
...ction to read your line. However, there seems to be no way to see how many characters it read. So you use fgetc:
char * getline(void) {
char * line = malloc(100), * linep = line;
size_t lenmax = 100, len = lenmax;
int c;
if(line == NULL)
return NULL;
for(;;) {
...
List columns with indexes in PostgreSQL
...constraint uk_test3ab unique (a, b));
List indexes and columns indexed:
select
t.relname as table_name,
i.relname as index_name,
a.attname as column_name
from
pg_class t,
pg_class i,
pg_index ix,
pg_attribute a
where
t.oid = ix.indrelid
and i.oid = ix.indexreli...
How to keep one variable constant with other one changing with row in excel
...out that you can toggle relative addressing for a formula in the currently selected cells with these keyboard shortcuts:
Windows: f4
Mac: CommandT
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