In C++, `std::set`s are a kind of associative container that stores unique elements, and in which the elements themselves are the keys.
Questions tagged [stdset]
294 questions
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votes
1 answer
Which is the fastest way to erase in set?
I read the cpp reference there are three ways to erase in std::set.
void erase (iterator position)
size_type erase (const value_type& val)
void erase (iterator first, iterator last)
Assuming I already know the iterator, which is faster, erasing…
jslee
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- 1
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votes
1 answer
Seg fault with default allocation std::set
I am trying to learn STL allocators for void*. Here is my code
#include
#include
class Test {
public:
std::set GetAllInformation() { return info_set_; }
private:
std::set info_set_;
};
int main() {
…
atulya
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votes
1 answer
In c++ code, set.erase(it) is halting execution, where it=set.begin() for a set of pairs, why is this happening?
Sorry for any inconvenience I am a beginner at C++ and was stuck with an empty set... Thank you for the helpful comments that helped me figure out what the problem was
I wrote a C++ code for a question in which I need to use Dijkstra's shortest path…
costheta_z
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votes
1 answer
Why the C++ set subtraction could not be easier?
I am completely aware that set_difference can subtract two sets and I am aware that operators are syntactic sugars. But, I am wondering why the standard library designers do not provide such a functionality so subtraction becomes such easy?
#include…
Kate
- 31
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votes
2 answers
How does this std::set initialization work?
I am having some trouble understanding how the std::set initialization works. I have the following code in a function:
std::map my_map = {
{16, 24},
{19, 29},
{15, 23},
{14, 22},
{13, 21},
{17, 28},
};
typedef…
-3
votes
1 answer
Task with inserting elements to list - tough a little
This is just a continuation of several past questions.
My function should return std::vector>
A group of names should be classified into teams for a game. Teams should be the same size, but this is not always possible unless n…
cpp_mountain
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votes
2 answers
std::map> here my_map[1] = std::set(); ---> what does this line serve
Below is my code, wanted to know what does the line my_map[1] = std::set(); serve?
std::map> my_map;
int main() {
int i = 10;
int *ptr = &i;
my_map[1] = std::set();
my_map[1].insert(ptr);
for…
user7809950
-3
votes
3 answers
Right way to remove an element in std::set
I have a graph class
struct Graph
{
list vertices;
};
int main()
{
Graph g;
// fill out graph
return 0;
}
I want to perform a Dijkstra-shortest-path-like algorithm. Step 1 would be creating a set out of all the nodes, which I…
ToniAz
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votes
2 answers
Find an element in std::set by a custom comparator
I created a class Route which I wanted to store in an std::set. A Route is indexed by an Id, so what I want is to be able to have an expression like
class RouteTemplate
{
Route *RouteTemplate::getRoute(const char *pId);
Route::ptr_set…
Devolus
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