Undirected graph

Description:

• All edges are undirected

Handshaking theorem:

• Let $G=(V,E)$ be an undirected graph with 𝑚 edges.
• Then $2m={\Sigma }_{v\in V}\text{deg}(v)$
• Also applies even if multiple edges and loops are present.
• Theorem:
  • An undirected graph has an even number of vertices of odd degreetheorem