👉 In graph theory and computer science, an "underedge" is a vertex in a directed graph that is adjacent to both its parent and its child vertices. In other words, it's a vertex with two children (if any) connected by edges pointing in opposite directions. For example: - The underedge of the vertex 1 in the graph G(4,2) represents the node 1 itself. - The underedge of the vertex 3 in the graph G(5,4
