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# std::make_pair

From cppreference.com
< cpp‎ | utility‎ | pair

Defined in header `<utility>` |  |

template< class T1, class T2 > std::pair<T1,T2> make_pair( T1 t, T2 u ); |  | (until C++11)
template< class T1, class T2 > std::pair<V1,V2> make_pair( T1&& t, T2&& u ); |  | (since C++11) (until C++14)
template< class T1, class T2 > constexpr std::pair<V1,V2> make_pair( T1&& t, T2&& u ); |  | (since C++14)

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

The deduced types `V1` and `V2` are std::decay<T1>::type and std::decay<T2>::type (the usual type transformations applied to arguments of functions passed by value) unless application of std::decay results in std::reference_wrapper<X> for some type `X`, in which case the deduced type is `X&`. | (since C++11)

### [edit] Parameters

t, u | - | the values to construct the pair from

### [edit] Return value

An std::pair object containing the given values.

### [edit] Example

Run this code

    #include <iostream>
    #include <utility>
    #include <functional>

    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 + 1) << ")\n";
    }

Output:

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

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