I'm trying to filter out invalid user inputs in a small C++ program using the following chunk of code: int selection = -1; while (!(selection >= 1 && selection <=4)) { cin >> selection; if (!(selection >= 1 && selection <=4)) { cout << "invalid selection!" << endl; cout << ...
hello, i need to execute an for loop till the queue is empty my code queue<string> q; for(int i=0;i<q.size(),i++) { // some operation goes here // some datas are added to queue } ...
I'm currently working on a numerical library that uses expression templates. Unfortunately I encountered a problem with my operator overloads. Consider the following stripped down example. #include <vector> namespace test { class test {}; template<class A, class B> class testExpr {}; template<class A, class B> tes...
Recently I wrote a family of functions for trimming leading and trailing whitespace off of an input string. As the concept of "whitespace" is locale-dependent, I realized that I would need to either pass in a const std::ctype<char_t> reference or a const std::locale reference and call std::use_facet<std::ctype<char_t> > on the const std:...
Hi I want to (multiply,add,etc) vector by scalar value for example myv1 * 3 , I know I can do a function with a forloop , but is there a way of doing this using STL function ? something like the {Algorithm.h :: transform function } ?? ...
How is this done in C++0x? std::vector<double> myv1; std::transform(myv1.begin(), myv1.end(), myv1.begin(), std::bind1st(std::multiplies<double>(),3)); Original question and solution is here. ...
std::vector<string> names; std::vector<string>::iterator start = names.begin(); std::vector<string>::iterator end = names.end(); sort (start,end); //are my start and end valid at this point? //or they do not point to front and tail resp? ...
Currently I am studying Standard Template Library (STL). In this program I am storing some long values in Associative Container and then sorting them according to unit's place (according to the number in unit's place). Code : #include <iostream> #include <set> #include <functional> using namespace std; class UnitLess { public: ...
Hi everybody! It's time for another 'how do i do this in c++ without loosing my grip'-question! This time: Considering the following code taken from cplusplus.com: template<class InputIterator, class OutputIterator> OutputIterator copy ( InputIterator first, InputIterator last, OutputIterator result ) { while (first!=last) *resul...
I am using C++ and i want to push strings in stack like push int in stacks. For Example 3."stackoverflow" 2."is" 1."Best" 0."site" at every index of stack I want to push a string. How can I do this? ...
Hi everybody! Last question before the weekend ... i promise ... :) Title says it all: is it possible to use the operators defined in glm::gtx::comparison in stl algorithms? Specifically i have this code: std::vector<glm::ivec3> vecA, vecB; // vectors with content bool result = std::equal(vecA.begin(), vecA.end(), vecB.begin()); ...
I've looked at different papers and here is the information that I've gathered: SGI implementation and C cords neither guarantee O(1) time concatenation for long ropes nor ~log N depth for shorter ones. Different sources contradict each other. Wikipedia claims O(1) concatenation. This page says that concatenation is O(1) only when one ...
I'm having trouble getting something to compile. I don't understand the error thrown out by the compiler. Some code to illustrate the problem is below. #include <map> using namespace std; class Thing { public: Thing(int n):val(n) {} bool operator < (const Thing& rhs) const { return val < rhs.val; } int ...
In C++ I have 2 STL vectors A and V. A has data and is able to change it, V only points to data but reads only and can't modify it. So if these two vectors are inside a class what will be the syntax of Variables definition assigning A reference into V get_A() and get_V() will it return a reference or a pointer? Also If I have other...
i want to find an object with O(logN) and also remove with O(log N) - but no go to balanced tree implementation.. any idea's for that? ...
Hi, I have this: //function definition //Point and Range are classes made of 2 ints Point barycenter_of_vector_in_range(vector<cv::Point> &points, cv::Range range); //In other place... vector<vector<Point> > tracks_; //it has some content for (vector< vector<Point> >::const_iterator track = tracks_.begin(); track != tracks_.end(); tr...
Possible Duplicates: Vector.erase(Iterator) causes bad memory access iterate vector, remove certain items as I go. Hi, I wrote this but I am get some errors when running it for (vector< vector<Point> >::iterator track = tracks_.begin(); track != tracks_.end(); track++) { if (track->empty()) { // if track is empty, r...
I have: std::list<Particle> particles; std::list<Particle>::iterator particleit; in my main.cpp. I need to declare both of these as extern in one of my class files, but my compiler gives me some error about a missing '>' when I try the straightforward way. How would I go about fixing this? ...
Hi! I need analog of Haskell's foldl function to fold any STL containers. Expected signature is like following: template Iterator, FoldingFunction, Result Result foldl( Iterator begin, Iterator end, FoldingFunction f, Result initValue); Standard STL has no such function. Does Boost have any? I know it's pretty simple to im...