std::make_pair() in C++

In C++, std::make_pair() is a standard library function that is used to construct a key-value pair from the given arguments. The type of the pair constructed is deduced automatically from the type of arguments. It is defined as a function template inside the <utility> header file.

Syntax of std:make_pair()

std::make_pair(key, value);

Parameters of make_pair()

• key: Represents the key for the pair object i.e. first value.
• value: Represents the value for the pair object i.e. second value.

Return Value of make_pair()

The make_pair() function returns an object of std::pair having first and second elements as key and value passed as argument.

Example of make_pair()

C++

// C++ program to illustrate
// std::make_pair() function in C++
#include <iostream>
#include <utility>
using namespace std;

int main()
{
    // Pair Declared
    pair<int, string> p1;

    // Pair Initialized using make_pair()
    p1 = make_pair(1, "GeeksforGeeks");

    // using it with auto type deduction
    auto p2 = make_pair("GeeksforGeeks", 1);

    // Pair Printed
    cout << "Pair 1: " << p1.first << ", " << p1.second
         << endl;

    cout << "Pair 2: " << p2.first << ", " << p2.second;

    return 0;
}

Output

Pair 1: 1, GeeksforGeeks
Pair 2: GeeksforGeeks, 1