I am trying to enumerate all the monitors in Windows 7, and according to MSDN, using the QueryDisplayConfig method is the correct way to do this. All of this code works fine, and returns a couple of arrays, one with paths and one with modes. However, it doesn't have the same monitor ID's as Windows. I am trying to build an array of all t...
Case One Say you have a little class: class Point3D { private: float x,y,z; public: operator+=() ...etc }; Point3D &Point3D::operator+=(Point3D &other) { this->x += other.x; this->y += other.y; this->z += other.z; } A naive use of SSE would simply replace these function bodies with using a few intrinsics. But would we e...
Different STL containers like vector, stack, set, queue, etc support different access methods on them. If you are coding for example in Notepad++ or vim, you have to continuously refer to the documentation to see what all methods are available, atleast I have to. Is there some good way of remembering which container supports which meth...
I am testing the speed of inserting multiple rows with a single INSERT statement. For example: INSERT INTO [MyTable] VALUES (5, 'dog'), (6, 'cat'), (3, 'fish) This is very fast until I pass 50 rows on a single statement, then the speed drops significantly. Inserting 10000 rows with batches of 50 take 0.9 seconds. Inserting 10000 rows ...
difference between pass by value result and pass by reference with c,c++ examples.... ...
I'm trying to find a significant memory leak (15MB at a time, but doing allocations like this on multiple places). I checked the most obvious places, and then used AQTime, but I still can't pinpoint it. Now I see 2 options left: 1) Use SetProcessWorkingSetSize: I've tried this but my process happily keeps on running when using up more t...
I've finished my poker game but now I want to make it look a bit better with displaying Spades, Hearts, Diamonds and Clubs. I tried this answer: http://stackoverflow.com/questions/2094366/c-printing-ascii-heart-and-diamonds-with-platform-independent Maybe stupid but I try: cout << 'U+2662' << endl; I don't know how to write it. ...
I am trying to create an offline registry in memory using the offreg.dll provided in the windows ddk 7 package. You can find out more information on the offreg.dll here: MSDN Currently, while attempting to read a value from an open registry hive / key I receive the following error: 234 or ERROR_MORE_DATA Here is the .h code that conta...
I am studying COM so there're some basic questions puzzling me... I know that IDL file is used to describe the method definitions (or the so called 'contract' between software modules), and the .H header files contains something like a method prototype, which looks similar to what the IDL is meant for. So, why are these two things coex...
hi all, why is that name of constructor is same as class name? thank you in advance ...
vector<int> l; for(int i=1;i<=10;i++){ l.push_back(i); } Now, for example, how do I change the 5th element of the vector to -1? I tried l.assign(4, -1); It is not behaving as expected. None of the other vector methods seem to fit. I have used vector as I need random access functionality in my code (using l.at(i)). ...
hi guys i'm trying to make a static library from a class but when trying to use it i always get errors with undefined references on anything. the way i proceeded was creating the object file like g++ -c myClass.cpp -o myClass.o and then packing it with ar rcs myClass.lib myClass.o there is something i'm obviously missing generaly...
#include<stdio.h> main() { long long int m,n,i,j; int t; scanf("%d",&t); while(t--) { scanf("%lld",&m); scanf("%lld",&n); long long int a[n+2]; for(i=0;i<=n;i++) { a[i]=1; } for(i=2;i<=sqrt(n);i++) { j=2; while((i*j)<=n) ...
I'm in a strange situation where I have a value of 0.5 and I want to convert the values from 0.5 to 1 to be a percentage and from 0.5 to 0 to be a negative percentage. As it says in the title 0.4 should be -20%, 0.3 should be -40% and 0.1 should be -80%. I'm sure this is a simple problem, but my mind is just refusing to figure it out :...
Okay so i need really FAST algorithm or code in C if you have any it would be nice. The task is to sum all numbers from 1 to N for a given number N (it can be negative number too), so i did the usual way (you know just summing with loop from 1 to N) but it's not fast enough - i need something faster, i guess that i need the fastest possi...
I'm not a professional programmer, so please don't hesitate to state the obvious. My goal is to use a std::multiset container (typedef EventMultiSet) called currentEvents to organize a list of structs, of type Event, and to have members of class Host occasionally add new Event structs to currentEvents. The structs are supposed to be sor...
Can anybody explain why this code does not generate a compiler error? class Foo { public: int _x; }; Foo getFoo() { Foo myfoo; myfoo._x = 10; return myfoo; } int _tmain() { // shouldn't this line of code be a compiler error? Foo& badfoo = getFoo(); return 0; } ...
Hi all, I made a private API that assumes that the address of the first member-object in the class will be the same as the class's this-pointer... that way the member-object can trivially derive a pointer to the object that it is a member of, without having to store a pointer explicitly. Given that I am willing to make sure that the co...
I've used a few profilers in the past and never found them particularly easy. Maybe I picked bad ones, maybe I didn't really know what I was expecting! But I'd like to know if there are any 'standard' profilers which simply drop in and work? I don't believe I need massively fine-detailed reports, just to pick up major black-spots. Ease o...
i recently came across a question about sequence points in c++ at this site what the code will output: int c=0; cout<<c++<<c; it was answered that the output is undefined and << is not a sequence point but still i want to know why does it that even if i compile it 25 times it still prints 01 ...