#include <bits/stdc++.h>
using namespace std;

int main()
{
    std::string str = "Salut";
    std::vector<std::string> v;
 
    // uses the push_back(const T&) overload, which means 
    // we'll incur the cost of copying str
    v.push_back(str);
    std::cout << "After copy, str is " << std::quoted(str) << '\n';
 
    // uses the rvalue reference push_back(T&&) overload, 
    // which means no strings will be copied; instead, the contents
    // of str will be moved into the vector.  This is less
    // expensive, but also means str might now be empty.
    v.push_back(std::move(str));
    cout << "After move, str is " << std::quoted(str) << '\n';
    cout << "After move, str size is " << str.size() << endl;
 
    std::cout << "The contents of the vector are { " << std::quoted(v[0])
                                             << ", " << std::quoted(v[1]) << " }\n";
}

// Possible output:

// After copy, str is "Salut"
// After move, str is ""
// The contents of the vector are { "Salut", "Salut" }