Who Knows Whom? When Anything Can Connect: Graphs

Find a person's friends in one step, in a network where anyone can know anyone and friendships loop back around: why a list of pairs and a tree both fall short, and the structure that fits, the graph, with one-way and two-way connections and weights.

Updated

Cheat sheet: Who Knows Whom? When Anything Can Connect: Graphs
Category
Data Structures
Level
Journeyman
Tags
data structures, Directed Graph, Edge, Graph, Vertex, Weighted Graph