childrenOf method
Implementation
Map<V, Vertex<V>> childrenOf(Map<V, Vertex<V>> vertices) {
return vertices.entries.fold({}, (a, c) {
final children = Map.fromEntries(graph
.childrenOf(c.value)
.entries
.where((entry) => !a.containsKey(entry.key)));
return {...a, ...children};
});
}