Skip to content
← All questions

What is the maximum number of edges in a strongly connected directed graph with n vertices?

The maximum number of edges in a strongly connected directed graph with n vertices is n(n−1)n(n-1). This corresponds to a complete directed graph where every pair of distinct vertices has edges in both directions.

Conditions

  • The graph is directed.
  • The graph is strongly connected.
  • The graph has n vertices.

Reasoning, step by step

  1. Identify the number of vertices n.
  2. Apply the formula for the maximum number of edges: n(n−1)n(n-1).
  3. Understand that this is twice the number of edges in an undirected complete graph, n(n−1)/2n(n-1)/2.

Example

For a directed graph with 5 vertices (n=5n=5), the maximum number of edges is 5(5−1)=205(5-1) = 20. The instructor explains this by noting that each pair of vertices can have two opposite-directed edges.

Common misconceptions

  • Thinking the maximum number of edges is n(n−1)/2n(n-1)/2, which applies to undirected graphs.
  • Assuming that a strongly connected graph cannot have the maximum number of edges.

Watch the explanation

Connected concepts

Explore next

Related questions

Find a method

↗
Meet the concept

↗
Meet the concept

↗

Answers are generated from source material and independently checked. Consult the original video or creator if something is unclear.