#include <vector>
#include <iostream>
 
class Foo
{
 public:
 Foo(int x) : data_(x)
 {
 std::cout << " constructing " << std::endl;
 }
 
 ~Foo()
 {
 std::cout << " destructing " << std::endl;
 }
 
 Foo& operator=(const Foo&) = default;
 Foo& operator=(Foo&&) = default;
 
 Foo(Foo&& other) noexcept : data_(std::move(other.data_))
 {
 std::cout << " Move constructing " << std::endl;
 }
 
 Foo(const Foo& other) noexcept : data_(other.data_)
 {
 std::cout << " Copy constructing " << std::endl;
 }
 
 private:
 int data_;
};
 
 
int main ( int argc, char *argv[])
{
 std::vector<Foo> v;
 v.reserve(2);
 v.emplace_back(1);
 std::cout << "Added 1" << std::endl;
 v.emplace_back(2);
 std::cout << "Added 2" << std::endl;
 v.emplace_back(3);
 std::cout << "Added 3" << std::endl;
 std::cout << "v size: " << v.size() << std::endl;
}

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