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What guarantees are there on the run-time complexity (Big-O) of LINQ methods?
...).
Distinct, GroupBy Join, and I believe also the set-aggregation methods (Union, Intersect and Except) use hashing, so they should be close to O(N) instead of O(N²).
Contains checks for an ICollection implementation, so it may be O(1) if the underlying collection is also O(1), such as a HashSet<...
How to determine CPU and memory consumption from inside a process?
...hysMemUsedByMe = pmc.WorkingSetSize;
CPU currently used:
#include "TCHAR.h"
#include "pdh.h"
static PDH_HQUERY cpuQuery;
static PDH_HCOUNTER cpuTotal;
void init(){
PdhOpenQuery(NULL, NULL, &cpuQuery);
// You can also use L"\\Processor(*)\\% Processor Time" and get individual CPU...
How to convert a char to a String?
I have a char and I need a String . How do I convert from one to the other?
12 Answers
...
How can I pad an int with leading zeros when using cout
...) << 25;
}
the output will be
00025
setfill is set to the space character (' ') by default. setw sets the width of the field to be printed, and that's it.
If you are interested in knowing how the to format output streams in general, I wrote an answer for another question, hope it is us...
How much is the overhead of smart pointers compared to normal pointers in C++?
...ude <thread>
uint32_t n = 100000000;
void t_m(void){
auto a = (char*) malloc(n*sizeof(char));
for(uint32_t i=0; i<n; i++) a[i] = 'A';
}
void t_u(void){
auto a = std::unique_ptr<char[]>(new char[n]);
for(uint32_t i=0; i<n; i++) a[i] = 'A';
}
void t_u2(void){
a...
Pass an array of integers to ASP.NET Web API?
...ctionContext.ActionArguments[_parameterName] = parameters.Split(Separator).Select(int.Parse).ToArray();
}
}
public char Separator { get; set; }
}
I am applying it like so (note that I used 'id', not 'ids', as that is how it is specified in my route):
[ArrayInput("id", Separator =...
Maximum number of characters using keystrokes A, Ctrl+A, Ctrl+C and Ctrl+V
...rate through for i up to n, doing two things: pressing A once and pressing select all + copy followed by paste j times (actually j-i-1 below; note the trick here: the contents are still in the clipboard, so we can paste it multiple times without copying each time). We only have to consider up to 4 c...
What are the main performance differences between varchar and nvarchar SQL Server data types?
... AND ([URLa] IS NULL OR [URLu] IS NULL))
);
In this model you only SELECT from the [URL] computed column. For inserting and updating, you determine which field to use by seeing if converting alters the incoming value, which has to be of NVARCHAR type:
INSERT INTO TableName (..., URLa, URLu)...
How to print a int64_t type in C
...t:
#include <stdio.h>
#include <stdint.h>
int main(int argc, char *argv[])
{
int64_t a = 1LL << 63;
uint64_t b = 1ULL << 63;
printf("a=%jd (0x%jx)\n", a, a);
printf("b=%ju (0x%jx)\n", b, b);
return 0;
}
Compiling this code with gcc -Wall -pedantic -...
Stack smashing detected
...ple in the following snippet:
#include <stdio.h>
void func()
{
char array[10];
gets(array);
}
int main(int argc, char **argv)
{
func();
}
The compiler, (in this case gcc) adds protection variables (called canaries) which have known values. An input string of size greater than ...