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c++ Programming Glossary: longWhy is processing a sorted array faster than an unsorted array? http://stackoverflow.com/questions/11227809/why-is-processing-a-sorted-array-faster-than-an-unsorted-array std sort data data arraySize Test clock_t start clock long long sum 0 for unsigned i 0 i 100000 i Primary loop for unsigned.. std sort data data arraySize Test clock_t start clock long long sum 0 for unsigned i 0 i 100000 i Primary loop for unsigned.. With this the next loop runs faster Arrays.sort data Test long start System.nanoTime long sum 0 for int i 0 i 100000 i Primary..
Most effective way for float and double comparison http://stackoverflow.com/questions/17333/most-effective-way-for-float-and-double-comparison above. It all depends on context. I have spent a long time tracing a bugs in a system that presumed a b if a b epsion.. example 4.0 2.0 will be the same as 1.0 1.0. This is as long as you do not do things that result in fractions 4.0 3.0 or..
What are the rules about using an underscore in a C++ identifier? http://stackoverflow.com/questions/228783/what-are-the-rules-about-using-an-underscore-in-a-c-identifier for corresponding functions that operate on float and long double arguments respectively. Names that begin with 'SIG' followed.. use underscore. After doing research on this article I no longer end my identifiers with '_t' as this is reserved by the POSIX..
Is it possible to write a C++ template to check for a function's existence? http://stackoverflow.com/questions/257288/is-it-possible-to-write-a-c-template-to-check-for-a-functions-existence typename T class has_helloworld typedef char one typedef long two template typename C static one test typeof C helloworld..
http://stackoverflow.com/questions/3106110/what-is-move-semantics constructor we can do anything we want with the source as long as we leave it in some valid state string string that string.. null. In effect we have stolen the data that originally belonged to the source string. Again the key insight is that under..
When should static_cast, dynamic_cast and reinterpret_cast be used? http://stackoverflow.com/questions/332030/when-should-static-cast-dynamic-cast-and-reinterpret-cast-be-used a base class but when casting downwards it can be used as long as it doesn't cast through virtual inheritance. It does not.. or reinterpret_cast will fail. Even then consider the longer more explicit option. C style casts also ignore access control..
http://stackoverflow.com/questions/4172722/what-is-the-rule-of-three alternative using a char and you should be convinced. As long as you stay away from raw pointer members the rule of three..
Undefined Behavior and Sequence Points http://stackoverflow.com/questions/4176328/undefined-behavior-and-sequence-points this question Disclaimer Okay. This answer is a bit long. So have patience while reading it. If you already know these..
What are Aggregates and PODs and how/why are they special? http://stackoverflow.com/questions/4178175/what-are-aggregates-and-pods-and-how-why-are-they-special improve this question How to read This article is rather long. If you want to know about both aggregates and POD's Plain Old.. have a default constructor and or a copy constructor as long as they are implicitly declared by the compiler and not explicitly..
http://stackoverflow.com/questions/589575/size-of-int-long-etc of int long etc I'm looking for detailed information regarding the size.. Here is what I get char 1 byte short 2 bytes int 4 bytes long 4 bytes float 4 bytes double 8 bytes I tried to find without.. reliable information stating the sizes of char short int long double float and other types I didn't think of under different..
Can a local variable's memory be accessed outside its scope? http://stackoverflow.com/questions/6441218/can-a-local-variables-memory-be-accessed-outside-its-scope force that causes your book to disappear when you are no longer authorized to be in the room. Nor is there a mysterious force.. have become entrenched. The first is to have some sort of long lived storage area where the lifetime of each byte in the storage.. storage when it is needed and reclaim it when it is no longer needed. The second is to have some sort of short lived storage..
Performance penalty for working with interfaces in C++? http://stackoverflow.com/questions/113830/performance-penalty-for-working-with-interfaces-in-c functions share improve this question Short Answer No. Long Answer It is not the base class or the number of ancestors a..
How to convert std::string to LPCSTR? http://stackoverflow.com/questions/1200188/how-to-convert-stdstring-to-lpcstr str.c_str gives you a const char which is an LPCSTR Long Pointer to Constant STRing means that it's a 32 bit pointer..
C++ templates Turing-complete? http://stackoverflow.com/questions/189172/c-templates-turing-complete Is this fact useful in practice Short Answer Sort of. Long Answer Yes but only if you are a template daemon. To turn out..
Why are Hexadecimal Prefixed as 0x? http://stackoverflow.com/questions/2670639/why-are-hexadecimal-prefixed-as-0x to specify the number base the x is an arbitrary choice. Long story In the 60's the prevalent programming number systems were..
In C++, is it still bad practice to return a vector from a function? http://stackoverflow.com/questions/3134831/in-c-is-it-still-bad-practice-to-return-a-vector-from-a-function or do C programmers consider it weird ugly abomination Long version In C 0x is this still considered bad form std vector..
Convert Lat/Longs to X/Y Co-ordinates http://stackoverflow.com/questions/4953150/convert-lat-longs-to-x-y-co-ordinates Lat Longs to X Y Co ordinates I have the Lat Long value of an small.. Lat Longs to X Y Co ordinates I have the Lat Long value of an small area in Melbourne 37.803134 145.132377 and.. 916 I would like to be able to convert using C the Lat Long to an X Y coordinate where the point would reflect the location...
Why should one not derive from c++ std string class? http://stackoverflow.com/questions/6006860/why-should-one-not-derive-from-c-std-string-class and the references are always the same size. Not so in C . Long story short don't use inheritance to tack on methods in C ...
Is multiplication and division using shift operators in C actually faster? http://stackoverflow.com/questions/6357038/is-multiplication-and-division-using-shift-operators-in-c-actually-faster share improve this question Short answer Not likely. Long answer Your compiler has an optimizer in it that knows how to..
Template Specialization VS Function Overloading http://stackoverflow.com/questions/7108033/template-specialization-vs-function-overloading story overload when you can specialise when you need to. Long story C treats specialisation and overloads very differently...
I don't want my Excel Add-In to return an array (instead I need a UDF to change other cells) http://stackoverflow.com/questions/8520732/i-dont-want-my-excel-add-in-to-return-an-array-instead-i-need-a-udf-to-change Declare Function SetTimer Lib user32 _ ByVal HWnd As Long _ ByVal nIDEvent As Long _ ByVal uElapse As Long _ ByVal lpTimerFunc.. Lib user32 _ ByVal HWnd As Long _ ByVal nIDEvent As Long _ ByVal uElapse As Long _ ByVal lpTimerFunc As Long _ As Long.. HWnd As Long _ ByVal nIDEvent As Long _ ByVal uElapse As Long _ ByVal lpTimerFunc As Long _ As Long Private Declare Function..
while (1) Vs. for (;;) Is there a speed difference? http://stackoverflow.com/questions/885908/while-1-vs-for-is-there-a-speed-difference 1 Vs. for Is there a speed difference Long version... A co worker asserted today after seeing my use of..
http://stackoverflow.com/questions/1627448/virtual-webcam-driver inputCat L Instance win32_utils CRegKey hKeyInstancesDir LONG rval openKey HKEY_CLASSES_ROOT regPath KEY_WRITE hKeyInstancesDir..
Is it reasonable to use std::basic_string<t> as a contiguous buffer when targeting C++03? http://stackoverflow.com/questions/2256160/is-it-reasonable-to-use-stdbasic-stringt-as-a-contiguous-buffer-when-targeti string immediately. Example DWORD valueLength 0 DWORD type LONG errorCheck RegQueryValueExW hWin32 value.c_str NULL type NULL..
Fast rectangle to rectangle intersection http://stackoverflow.com/questions/2752349/fast-rectangle-to-rectangle-intersection it seems to be written in an ancient form of C . struct LONG left LONG top LONG right LONG bottom RECT bool IntersectRect.. to be written in an ancient form of C . struct LONG left LONG top LONG right LONG bottom RECT bool IntersectRect const RECT.. in an ancient form of C . struct LONG left LONG top LONG right LONG bottom RECT bool IntersectRect const RECT r1 const..
How to read a value from the Windows registry http://stackoverflow.com/questions/34065/how-to-read-a-value-from-the-windows-registry code Include the library dependency Advapi32.lib HKEY hKey LONG lRes RegOpenKeyExW HKEY_LOCAL_MACHINE L SOFTWARE Perl 0 KEY_READ.. L bad GetStringRegKey hKey L strKeyDefaultValue L bad LONG GetDWORDRegKey HKEY hKey const std wstring strValueName DWORD.. DWORD dwBufferSize sizeof DWORD DWORD nResult 0 LONG nError RegQueryValueExW hKey strValueName.c_str 0 NULL reinterpret_cast..
Reading from a text field in another application's window http://stackoverflow.com/questions/352236/reading-from-a-text-field-in-another-applications-window error checks HWND hwnd HWND 0x00310E3A char szBuf 2048 LONG lResult lResult SendMessage hwnd WM_GETTEXT sizeof szBuf sizeof..
GetDIBits and loop through pixels using X, Y http://stackoverflow.com/questions/3688409/getdibits-and-loop-through-pixels-using-x-y pixel. The high byte in each DWORD is not used. Since a MS LONG is exactly 32 bit long the size of a DWORD you do not have to..
c++ get registry key returns only one char http://stackoverflow.com/questions/4483087/c-get-registry-key-returns-only-one-char char data 100 DWORD datasize sizeof data sizeof char LONG rc RegOpenKeyEx HKEY_LOCAL_MACHINE L SOFTWARE Microsoft Windows..
C++ cross-compiler from Windows to Linux http://stackoverflow.com/questions/4769968/c-cross-compiler-from-windows-to-linux using a Makefile. NOTE Building the cross compiler takes a LONG time. I found a prebuilt one here but it's several years old...
Is Critical Section always faster? http://stackoverflow.com/questions/853316/is-critical-section-always-faster RTL_CRITICAL_SECTION PRTL_CRITICAL_SECTION_DEBUG DebugInfo LONG LockCount LONG RecursionCount HANDLE OwningThread HANDLE LockSemaphore.. PRTL_CRITICAL_SECTION_DEBUG DebugInfo LONG LockCount LONG RecursionCount HANDLE OwningThread HANDLE LockSemaphore ULONG_PTR.. RecursionCount HANDLE OwningThread HANDLE LockSemaphore ULONG_PTR SpinCount c winapi synchronization critical section ..
Determine path to registry key from HKEY handle in C++ http://stackoverflow.com/questions/937044/determine-path-to-registry-key-from-hkey-handle-in-c code snippet. #include windows.h #include string typedef LONG NTSTATUS #ifndef STATUS_SUCCESS #define STATUS_SUCCESS NTSTATUS.. KeyHandle int KeyInformationClass PVOID KeyInformation ULONG Length PULONG ResultLength NtQueryKeyType func reinterpret_cast.. KeyInformationClass PVOID KeyInformation ULONG Length PULONG ResultLength NtQueryKeyType func reinterpret_cast NtQueryKeyType..
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