I want a program that creates an undetermined amount of lists. The size of each list is fixed, but I can't determine at compile time how many lists am I going to need.
I understand I cannot create a vector of arrays. I also understand I can use a vector of vectors, but I wonder if this is the best efficient way to do it considering the fact I need to reserve a fixed amount of memory each time I need a new array.
Erm, you can use a vector of arrays, for example,
std::vector<std::array<T, N>> some_vec;
<array<array<int,2>, 64>> create a vector of a 2x64 elements?
vector<array<array<short,2>,64>> sol and I want to copy the stack stack<array<short,2> lifo to the first element in vector sol. Is this correct? sol[0]=lifo;
std::vector<std::array<T, N> > some_vec; (note the space between the two >), otherwise the compiler will complain about invalid use of the >> operator.std::array implies c++11, which means that you no longer need spaces between the angle brackets! You should upgrade your compiler (or standard!)@Nim is right, but I cannot upvote yet :p Also his solution is C++11.
Another alternative which is to be preferred over std::vector<std::vector<T> > is to have one vector with the dimensions X * Y. Then you can access your elements with v[y * Y + x];
This works with all versions of C++ and should be just as efficient as the std::vector<std::array<T, N> > solution.
std::arrayas its underlying storage. If you can't use C++11, you are probably better off using vectors rather than legacy C arrays. Any performance loss will probably be utterly insignificant.