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How to Generate unique file names in C#
... exists), I fall back to GUIDs.
Update:
Recently, I've also use DateTime.Now.Ticks instead of GUIDs:
var myUniqueFileName = string.Format(@"{0}.txt", DateTime.Now.Ticks);
or
var myUniqueFileName = $@"{DateTime.Now.Ticks}.txt";
The benefit to me is that this generates a shorter and "nicer loo...
Effects of the extern keyword on C functions
...ar.c.
Here is foo.c
#include <stdio.h>
volatile unsigned int stop_now = 0;
extern void bar_function(void);
int main(void)
{
while (1) {
bar_function();
stop_now = 1;
}
return 0;
}
Now, here is bar.c
#include <stdio.h>
extern volatile unsigned int stop_now;
void b...
Computational complexity of Fibonacci Sequence
I understand Big-O notation, but I don't know how to calculate it for many functions. In particular, I've been trying to figure out the computational complexity of the naive version of the Fibonacci sequence:
...
How do I install ASP.NET MVC 5 in Visual Studio 2012?
...udio 2012 Express for Web.
You can download and start using these features now.
The download link is to a Web Platform Installer that will allow you to start a new MVC5 project from VS2012.
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PHP append one array to another (not array_push or +)
...', 'b');
$b = array('c', 'd');
$merge = array_merge($a, $b);
// $merge is now equals to array('a','b','c','d');
Doing something like:
$merge = $a + $b;
// $merge now equals array('a','b')
Will not work, because the + operator does not actually merge them. If they $a has the same keys as $b, it...
What is the difference between shallow copy, deepcopy and normal assignment operation?
...llow copy:
d = copy.copy(c)
print id(c) == id(d) # False - d is now a new object
print id(c[0]) == id(d[0]) # True - d[0] is the same object as c[0]
Using a deep copy:
d = copy.deepcopy(c)
print id(c) == id(d) # False - d is now a new object
print id(c[0]) == id(d[0]) #...
How to check if a number is a power of 2
...that
is, the result is true if and only if both its operands are true.
Now let's take a look at how this all plays out:
The function returns boolean (true / false) and accepts one incoming parameter of type unsigned long (x, in this case). Let us for the sake of simplicity assume that someone ...
Is std::vector so much slower than plain arrays?
...d::vector<Pixel> pixels(dimensions * dimensions, Pixel(255,0,0));
Now doing the same timing again:
g++ -O3 Time.cpp -I <MyBoost>
./a.out
UseVector completed in 2.216 seconds
The vector now performance only slightly worse than the array. IMO this difference is insignificant...
How to extract the year from a Python datetime object?
...etime.today().year
or even (as Lennart suggested)
a = datetime.datetime.now().year
or even
a = datetime.date.today().year
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Can a class member function template be virtual?
... just indirection, and there is no "runtime figuring out" involved, it is known during compile time that the function to be called is the one pointed to by the n-th pointer in the vtable. "Figuring out" implies there are type checks and such, which is not the case. Once the run-time system figured o...