Question

Is it possible to use the std::array<class T, std::size_t N> as a private attribute of a class but initialize its size in the constructor of the class?

class Router{
    std::array<Port,???> ports; //I dont know how much ports do will this have
public:
    Switch(int numberOfPortsOnRouter){
        ports=std::array<Port,numberOfPortsOnRouter> ports; //now I know it has "numberOfPortsOnRouter" ports, but howto tell the "ports" variable?
    }
}

I might use a pointer, but could this be done without it?

Answer 1

No, the size must be known at compile time. Use std::vector instead.

class Router{
    std::vector<Port> ports;
public:
    Switch(int numberOfPortsOnRouter) : ports(numberOfPortsOnRouter) {
    }
};