Can there be multiple parents and/or multiple roots for a DAG?
Can there be multiple parents and/or multiple roots for a DAG?
A DAG is a graph that flows in one direction, where no element can be a child of itself. You can still have multiple children and multiple parents for a single node of the graph.
A graph is formed by a collection of vertices and edges, where the vertices are structureless objects that are connected in pairs by edges. In the case of a directed graph, each edge has an orientation, from one vertex to another vertex. A path in a directed graph can be described by a sequence of edges having the property that the ending vertex of each edge in the sequence is the same as the starting vertex of the next edge in the sequence; a path forms a cycle if the starting vertex of its first edge equals the ending vertex of its last edge. A directed acyclic graph is a directed graph that has no cycles.
Source: Wikipedia
At the very minimum, a directed acyclic graph must have: