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c++ Programming Glossary: someWhy 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 Here is a piece of C code that seems very peculiar. For some strange reason sorting the data miraculously speeds up the code.. array faster than an unsorted array The code is summing up some independent terms the order should not matter. java c performance.. to optimize the branch into a conditional move you can try some hacks if you are willing to sacrifice readability for performance...
Why is “using namespace std;” considered bad practice? http://stackoverflow.com/questions/1452721/why-is-using-namespace-std-considered-bad-practice Quux into your global namespace. This is going to take some effort to fix especially if the function parameters happen to..
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 identifier It's common in C to name member variables with some kind of prefix to denote the fact that they're member variables.. reserved symbols are defined here. The restrictions are somewhat more nuanced than those above. share improve this answer..
What is the slicing problem in C++? http://stackoverflow.com/questions/274626/what-is-the-slicing-problem-in-c of a base class thereby losing part of the information some of it is sliced away. For example class A int foo class B public..
What is the copy-and-swap idiom? http://stackoverflow.com/questions/3279543/what-is-the-copy-and-swap-idiom gone For a strong exception guarantee it would need to be something akin to dumb_array operator const dumb_array other if this.. guideline is as follows if you're going to make a copy of something in a function let the compiler do it in the parameter list... will be able to do the same after swapping. Note that some compilers do not support constructor delegation in this case..
What can I use to profile C++ code in Linux? http://stackoverflow.com/questions/375913/what-can-i-use-to-profile-c-code-in-linux times and each time look at the call stack. If there is some code that is wasting some percentage of the time 20 or 50 or.. at the call stack. If there is some code that is wasting some percentage of the time 20 or 50 or whatever that is the probability.. a sample. Another objection I often hear is It will stop someplace random and it will miss the real problem . This comes from..
http://stackoverflow.com/questions/4172722/what-is-the-rule-of-three more complicated because the target object is already in some valid state that needs to be dealt with. Since we declared neither.. will implicitly declare these member functions for some class types when the program does not explicitly declare them...
Undefined Behavior and Sequence Points http://stackoverflow.com/questions/4176328/undefined-behavior-and-sequence-points What are side effects Evaluation of an expression produces something and if in addition there is a change in the state of the.. it is said that the expression its evaluation has some side effect s . For example int x y where y is also an int In..
What are the differences between pointer variable and reference variable in C++? http://stackoverflow.com/questions/57483/what-are-the-differences-between-pointer-variable-and-reference-variable-in-c address with the original variable but also takes up some space on the stack. Since a reference has the same address as.. can be bound to temporaries. Pointers cannot not without some indirection const int x int 12 legal C int y int 12 illegal..
Where and why do I have to put the “template” and “typename” keywords? http://stackoverflow.com/questions/610245/where-and-why-do-i-have-to-put-the-template-and-typename-keywords on it. I also know that I should be able to add template somewhere to tell the compiler that inUnion is a template id. But.. class or typedef. Dependencies In template declarations some constructs have different meanings depending on what template.. example typename t template iterator int value_type v In some cases the keywords are forbidden as detailed below On the name..
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 you to break the rules of the system. If you try to do something illegal and foolish like going back into a room you're.. techniques have become entrenched. The first is to have some sort of long lived storage area where the lifetime of each byte.. is the period of time when it is validly associated with some program variable cannot be easily predicted ahead of time. The..
Finding current executable's path without /proc/self/exe http://stackoverflow.com/questions/1023306/finding-current-executables-path-without-proc-self-exe c c linux osx executable share improve this question Some OS specific interfaces Mac OS X _NSGetExecutablePath man 3 dyld.. of the executable or a name that was found using PATH . Some shells including bash and ksh set the environment variable _..
System(“pause”); - Why is it wrong? http://stackoverflow.com/questions/1107705/systempause-why-is-it-wrong as something that should not be done in varying degrees. Some people say it is fine to use. Some say it is only to be used.. in varying degrees. Some people say it is fine to use. Some say it is only to be used when you are locked in your room and.. when you are locked in your room and no one is watching. Some say that they will personally come to your house and kill you..
Why isn't sizeof for a struct equal to the sum of sizeof of each member? http://stackoverflow.com/questions/119123/why-isnt-sizeof-for-a-struct-equal-to-the-sum-of-sizeof-of-each-member is important to understand how the compilers align data. Some compilers have command line settings and or special #pragma..
http://stackoverflow.com/questions/1265039/using-std-namespace views on using 'using' with respect to the std namespace. Some say use ' using namespace std ' other say don't but rather prefix..
What open source C++ static analysis tools are available? [closed] http://stackoverflow.com/questions/141498/what-open-source-c-static-analysis-tools-are-available analysis tools that anyone knows of and can be recommended Some related links. C static code analysis tool on Windows http en.wikipedia.org..
Variable length arrays in C++? http://stackoverflow.com/questions/1887097/variable-length-arrays-in-c adding it to the C standard and if so why it was omitted Some potential reasons Hairy for compiler vendors to implement Incompatible..
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 includes errno math_errhandling setjmp and va_end . Some additional classes of identifier names are reserved for future..
Dynamically allocating an array of objects http://stackoverflow.com/questions/255612/dynamically-allocating-an-array-of-objects useful rule of 4 but I really suggest reading them all. Some are good succinct statements of what's wrong and some point..
Regular cast vs. static_cast vs. dynamic_cast http://stackoverflow.com/questions/28002/regular-cast-vs-static-cast-vs-dynamic-cast sequence would give you a compile time error for that. Some people prefer c style casts because of their brevity. I use..
http://stackoverflow.com/questions/408670/stack-static-and-heap-in-c how to correctly handle their dynamic memory allocations. Some other languages like Python would be horrible without GC so..
Pass by Reference / Value in C++ http://stackoverflow.com/questions/410593/pass-by-reference-value-in-c argument itself but rather the object being referenced . Some other say that pass by reference means that the object can't.. sample obj calls 3 sample oj_c calls 2 sample1 obj calls 4 Some people would claim that 1 and 3 are pass by reference while..
http://stackoverflow.com/questions/4172722/what-is-the-rule-of-three that manage resources is hard. Noncopyable resources Some resources cannot or should not be copied such as file handles.. person operator const person that delete The rule of three Sometimes you need to implement a class that manages a resource...
What is the proper declaration of main? http://stackoverflow.com/questions/4207134/what-is-the-proper-declaration-of-main int main int argc char argv int main int argc char argv Some implementations may allow other types and numbers of parameters..
Where and why do I have to put the “template” and “typename” keywords? http://stackoverflow.com/questions/610245/where-and-why-do-i-have-to-put-the-template-and-typename-keywords parsed as an expression. So the draft Standard says at 3.7 Some names denote types or templates. In general whenever a name.. template typename T struct derive_from_Has_type typename SomeBase T type In using declarations it's not possible to use template.. solution. template typename T struct derive_from_Has_type SomeBase T using SomeBase T template type error using typename SomeBase..
Unicode encoding for string literals in C++11 http://stackoverflow.com/questions/6796157/unicode-encoding-for-string-literals-in-c11 a Unicode string does not mean the number of codepoints. Some code points are combining characters an unfortunate name which..
How do I expand a tuple into variadic template function's arguments? http://stackoverflow.com/questions/687490/how-do-i-expand-a-tuple-into-variadic-template-functions-arguments but there is very little documentation on the subject. Some people suggest hand written recursive hacks but the true value..
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