Graph

A graph consists of vertices (or nodes) and edges that connect them. Edges may be directed or undirected, and they may include weights such as distance or cost.

The tree in Tree cannot represent the final help desk requirement: one player report may relate to several reports, and those reports may connect back to the same incident. A graph models those many-to-many relationships.

An adjacency list is a common representation:

connections = empty map
connections["A"] = ["B", "C"]
connections["B"] = ["A"]

Graphs model related support incidents. Breadth-first and depth-first traversals usually take O(V + E) with an adjacency list, where V is the number of vertices and E is the number of edges. A traversal must track visited IDs because the graph may contain cycles.

See Graph examples for runnable examples in supported programming languages.