Implementing copy c'tor for shared ptr vector?

Question

I want to write a copy c'tor to my class which contains a list of shared ptrs like this:

    std::vector<std::shared_ptr<Character>> board;

If I want he copy constructor to make copies of all of the Characters, Is is enough in my copy c'tor to write the following:

Game::Game(const Game &other): dimensions(other.dimensions), board(dimensions.getRow()*dimensions.getCol()) {
    int board_size= dimensions.getRow()*dimensions.getCol();
    for (int i=0;i<board_size;++i)
    {
        this->board[i]=other.board[I];  //or *(this.board[I]=*other.board[I];        
    }
}

plus, should I write copy c'tor in Character class? Please Note I have 2 questions,

Answer 1

Normally, you wouldn't copy characters, so the obvious change is simply

Game::Game(const Game &other): dimensions(other.dimensions), board(other.board) {}

Just let the vector copy itself. But since this is the default. You don't need anything custom so instead, in your class definition, just use

Game(const Game &other) = default;
Game(Game &&other) = default;

And then you know it's fast, accurate, and bug-free.

---

Since you say you want copies of characters, that takes a little more effort. Note that this only works if the `Character` class is not derived from.

Game::Game(const Game &other): dimensions(other.dimensions) {
    int board_size= dimensions.getRow()*dimensions.getCol();
    board.reserve(board_size);
    for (int i=0;i<board_size;++i)
    {
        board[i].push_back(std::make_shared<Character>(*other[i]));      
    }
}