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Showing content from https://en.cppreference.com/w/cpp/language/../algorithm/../ranges/../utility/pair/make_pair.html below:

std::make_pair - cppreference.com

template< class T1, class T2 > std::pair<T1, T2> make_pair( T1 x, T2 y ); (until C++11) template< class T1, class T2 > std::pair</*V1*/, /*V2*/> make_pair( T1&& x, T2&& y ); (since C++11)
(constexpr since C++14)
(until C++20) (since C++20)

Creates a std::pair object, deducing the target type from the types of arguments.

[edit] Parameters x, y - the values to construct the pair from [edit] Return value [edit] Example

#include <functional>
#include <iostream>
#include <utility>
 
int main()
{
    int n = 1;
    int a[5] = {1, 2, 3, 4, 5};
 
    // build a pair from two ints
    auto p1 = std::make_pair(n, a[1]);
    std::cout << "The value of p1 is "
              << '(' << p1.first << ", " << p1.second << ")\n";
 
    // build a pair from a reference to int and an array (decayed to pointer)
    auto p2 = std::make_pair(std::ref(n), a);
    n = 7;
    std::cout << "The value of p2 is "
              << '(' << p2.first << ", " << *(p2.second + 2) << ")\n";
}

Output:

The value of p1 is (1, 2)
The value of p2 is (7, 3)

[edit] Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR Applied to Behavior as published Correct behavior LWG 181 C++98 the parameter types were const-reference
types, which made passing arrays impossible changed these
types to value types

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