CompleteGraph

CompleteGraph[n] creates a complete graph $K_n$ with n vertices where every vertex is connected to every other.

Examples

Create complete graphs:

CompleteGraph[5]

(* Complete bipartite graph K_{3,3} *)
CompleteGraph[{3, 3}]

(* Styled complete graph *)
CompleteGraph[6, GraphStyle -> "DiagramBlue"]

Please visit the official Wolfram Language Reference for more details.