Trying to connect two different types of structures to create linked lists

2017-06-30

An answer to this question on Stack Overflow.

Question

I'm looking for a way to connect nodes created by different structures to make linked lists and things like that. I tried several ways but I was not able to. Can you help me?

Here is my code:

struct nodeA{
    int somedata;
    nodeA* next;
};
struct nodeB{
    int someData;
    nodeB* next;
    nodeB* someAnotherNode;
};
int main(){
    nodeA* A0 = new nodeA; //Just creating some nodes... 
    nodeA* A1 = new nodeA; 
    nodeA* A2 = new nodeA;
    nodeB* B0 = new nodeB;
    A0 -> next = A1; //I can connect these nodes
    A1 -> next = A2; //in this way.
    A2 -> next = B0; //but, I can't do that!
 
    return 0;
}

Answer

Use classes and polymorphism:

class NodeA {
 public:
  int somedata;
  NodeA* next;
};
class NodeB : public NodeA {
  NodeB* someAnotherNode;
};
int main(){
    NodeA* A0 = new NodeA; //Just creating some Nodes... 
    NodeA* A1 = new NodeA; 
    NodeA* A2 = new NodeA;
    NodeB* B0 = new NodeB;
    A0 -> next = A1; //I can connect these Nodes
    A1 -> next = A2; //in this way.
    A2 -> next = B0; //but, I *can* do that!
    return 0;
}