A std::pair is an ordered, heterogeneous sequence of exactly two objects (it is a special case of std::tuple).
std::pair is a part of the C++ Standard Library, defined in the header <utility>.
Questions tagged [std-pair]
776 questions
0
votes
1 answer
How to insert a pair of elements as single elements in a set container?
My simple code is like this :
#include
#include
using namespace std;
void main() {
set myset;
myset.insert(pair("abc","def"));
cout<
Biswajit
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votes
2 answers
0
votes
1 answer
Unpacking std::pair>> to tuple
So I'm trying to come up with a function which converts a;
std::pair>
data type, into a std::tuple;
std::tuple
It should work in the general case, with an arbitrary number of mixed type arguments, the format for the pairs…
Skeen
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1 answer
How to fill and access to std::map, funcPtr>?
I would like to know how to fill this type of map and mainly the way to access to the function pointer.
The map :
enum enum1
{
val11,
val12,
val13
};
enum enum2
{
val21,
val22,
val23
};
typedef…
Elfayer
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votes
1 answer
How to populate a mapped multimap?
I have the following mapped multimap :
map>> modCreAlt;
I am trying to insert a line in it :
int priority = ... ;
string alertInv = ... ;
string upperAlertInv = ... ;
modCreAlt.insert(make_pair(42,…
Pierre Espenan
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0
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3 answers
std::make_pair: "cannot convert ‘int*’ to ‘std::pair*’ in initialization"
In below listed function, I am trying create a pointer to an std::pair object where I get a compilation error shown at the bottom of this message (The related line number has been marked in the code snippet below). Could you please tell me what's…
F. Aydemir
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0
votes
2 answers
'std::pair' : use of class template requires template argument list
I'm trying to create an unordered_map whose key would be a member of the Gdiplus::Color class and a float but i can't figure why i can't do this. This is my declaration
std::unordered_map
Michael Afonso
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2 answers
Is there any performance loss for tuple with only 2 elements?
Compared with pair, is there any performance loss for tuple with only 2 elements?
user1899020
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votes
3 answers
How to change pair (> and <) operators behavior?
I'm trying to sort a vector< pair > but i want to change the behavior of the comparison operators of the pair type , so that if the first values equal and it'a comparing with (>) operator, i want it to compare the second value with (<)…
Ali Essam
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4 answers
How can you pass a vector > into a function?
If I try to declare the function as void some_function(vector > theVector), I get an error (presumably from the comma after "pair
#include…
Bob John
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2 answers
Accessing a nested pair
To take apart a pair, the following can be done
boost::bind(&std::pair::second, _1); // returns the value of a pair
What about using combinations of different containers, how can a nested pair be accessed?
For example when I wanted to partition a…
Peter Nimmo
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0
votes
2 answers
Using Node in Map, C++
class MtmMap {
public:
class Pair {
public:
Pair(const KeyType& key, const ValueType& value) :
first(key),
second(value) { }
const KeyType first;
…
Christine
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0
votes
1 answer
Pointer in a pair in C++
I need to return an array and it's size:
pair load(string path,int * memory){
ifstream handle;
int container;
int size = 0;
if(!handle){
QMessageBox::warning(0, QString(""), "file cannot be loaded");
…
Ben
- 3,989
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0
votes
2 answers
C++ heap sort of vector
I can not figure out where I'm having my problem with my heap sort.
The program takes a filename from the command line, imports the words into a vector then that vector is turned into a vector pair of vector where string is the word and…
Ryan
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votes
1 answer
Poor performance of GNU C++ compiler while sorting vector of pairs, compared with Intel
I have a vector of pairs in my program, which I need to sort. Something as:
std::vector > temp;
...
std::sort(temp.begin(), temp.end());
I performed some measurements and found out that for vector of size something over…
Daniel Langr
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