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Randomize a List
What is the best way to randomize the order of a generic list in C#? I've got a finite set of 75 numbers in a list I would like to assign a random order to, in order to draw them for a lottery type application.
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Is it safe to remove selected keys from map within a range loop?
...r key := range m {
if key.expired() {
delete(m, key)
}
}
And the language specification:
The iteration order over maps is not specified and is not guaranteed to be the same from one iteration to the next. If map entries that have not yet been reached are removed during iteratio...
INSERT INTO … SELECT FROM … ON DUPLICATE KEY UPDATE
... before the equals references the columns named in the INSERT INTO clause, and the second part references the SELECT columns.
INSERT INTO lee(exp_id, created_by, location, animal, starttime, endtime, entct,
inact, inadur, inadist,
smlct, smldur, smldist,
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promise already under evaluation: recursive default argument reference or earlier problems?
...1, f..=f){ g.(1,T, f.=f..) }? In cases with more recursions, is it a good and safe practice adding more .? (2) if f is a non-function argument, for example g <- function(x, T, f=f){ exp(-fx/T) }* and test<- function(g.=g, T=1, f=f){ g.(1,T, f=f.) }, will using the same name for both formal a...
What does an Asterisk (*) do in a CSS selector?
I found this CSS code and I ran it to see what it does and it outlined EVERY element on the page,
5 Answers
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Type erasure techniques
... erasure techniques in C++ are done with function pointers (for behaviour) and void* (for data). The "different" methods simply differ in the way they add semantic sugar. Virtual functions, e.g., are just semantic sugar for
struct Class {
struct vtable {
void (*dtor)(Class*);
vo...
Creating an empty list in Python
... Why does list('') give [] instead of ['']?
– Chris_Rands
Sep 20 '18 at 10:18
This is because this func make list from...
Is there a standard sign function (signum, sgn) in C/C++?
I want a function that returns -1 for negative numbers and +1 for positive numbers.
http://en.wikipedia.org/wiki/Sign_function
It's easy enough to write my own, but it seems like something that ought to be in a standard library somewhere.
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how to solve “ruby installation is missing psych” error?
...3. even though it was successfully installed, it complained about libyaml. and now every time i wanna install a gem (say rails) this warning shows up:
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git -> show list of files changed in recent commits in a specific directory
In Subversion svn log is the command to display commit log messages -- for details see the online manual at http://svnbook.red-bean.com/en/1.7/svn.ref.svn.c.log.html
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