C/C++ implementation of a Directed Acyclic Graph

Question

As novice, I m trying to generate a DAG with C (or C++).

struct Node
{
    Link *incomingEdge, *outgoingEdge;
};

struct Link
{

    Node *origin, *destination;

};

simply in my code there are only one incoming and outgoing edges for each node. However, a node could have several incident edges. Moreover, number of incident edges might change for each node.

how can I generate different number of pointers for each node ?

assume that I have;

nodeA with 5 incoming edges and 4 outgoing edges. nodeB with 3 incoming edges and 6 outgoing edges.

so number of pointers are changing for each node.

Answer 1

考虑使用指针向量

std::vector<Link *> incomingEdge;

Answer 2

It depends what you need. The graph is completely desccribed by the edges, so the easy answer is, omit *incomingEdge, *outgoingEdge from the node definition. But a linked list or an appropriate container from std:: of adjecent nodes will be probably be better for the algorithms you are going to implement.