graph

type EnumerableGraph[Node comparable, Edge any] interface {
	Graph[Node, Edge]
	AllNodes() iter.Seq[Node]
}

type EnumerableSimpleGraph[Node comparable, Edge any] interface {
	SimpleGraph[Node, Edge]
	AllNodes() iter.Seq[Node]
}

type Graph[Node comparable, Edge any] interface {
	// TODO return iterator?
	// TODO it's useful to be able to tell if a given node
	// is actually part of the graph or not. Could
	// say that returning nil slice signifies non-presence,
	// or (probably better) return ([]Edge, bool).
	EdgesFrom(Node) ([]Edge, bool)
	Nodes(Edge) (from, to Node)
	CmpNode(n0, n1 Node) int
}

type Simple[Node cmp.Ordered] struct {
	// contains filtered or unexported fields
}

type SimpleGraph[Node comparable, Edge any] interface {
	Graph[Node, Edge]
	Edge(Node) (Edge, bool)
}

type Weighted[Node comparable, Edge any] interface {
	Graph[Node, Edge]

	// EdgeWeight returns the weight of the given edge.
	EdgeWeight(Edge) float64
}