Question

Oftentimes in a program I am going to write, a user’s action is used to create a new instance of a class. I don’t know how many instances I will need, so how can I create instances at runtime and have a way to access each one individually? I have searched the forums, but I can’t understand any of the answers that have been given (I am still new to C++)

Answer 1

You can create an array (or vector) of classes, add any number of object instances to it, and access them using [] operator

#include <vector>

class A  // class declaration
{
  public:
    A();
    void print();
};

vector <A> v;     // creating vector
v.push_back(A()); // adding instance 0
v.push_back(A()); // adding instance 1
v[1].print(); // accessing instance 1