#include <iostream>
#include <vector>
 
 
struct Element
{
    Element(int number) :
            number_ID(number)
    {
        std::cout << "Element number " << number_ID
                  << " is being constructed\n";
    }
    Element(const Element &src) :
            number_ID(src.number_ID)
    {
        std::cout << "Element number " << number_ID << " is being copied\n";
    }
    Element(const Element &&src) :
            number_ID(src.number_ID)
    {
        std::cout << "Element number " << number_ID << " is being moved\n";
    }
    ~Element()
    {
        std::cout << "Element number " << number_ID << " is being destroyed\n";
    }
 
    Element& operator=(const Element &src)
    {
        number_ID = src.number_ID;
        std::cout << "Element number " << number_ID << " is being assigned\n";
        return *this;
    }
    Element& operator=(Element &&src)
    {
        number_ID = src.number_ID;
        std::cout << "Element number " << number_ID << " is being move assigned\n";
        return *this;
    }
 
    int number_ID;
};
 
void createVector()
{
    std::vector<Element> objArr;
    objArr.reserve(10);        // So it doesn't have to reallocate
 
    objArr.emplace_back(1);
    objArr.emplace_back(2);
    objArr.emplace_back(3);
    objArr.emplace_back(4);
 
    objArr.erase(objArr.begin()); // When I erase the first element only element 4 has destructor called
}
 
int main()
{
    createVector();
}
 

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