Tree Concepts: Difference between revisions
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# G is acyclic and │E│ = │V│ - 1. | # G is acyclic and │E│ = │V│ - 1. | ||
# G is acyclic, but if any edge is added to E, the resulting graph contains a cycle. | # G is acyclic, but if any edge is added to E, the resulting graph contains a cycle. | ||
=Forest= | |||
If the undirected graph is acyclic, but [[Graph_Concepts#Connectivity_and_Graph_Components|disconnected]], it is a [[Graph_Concepts#Forest|forest]]. | If the undirected graph is acyclic, but [[Graph_Concepts#Connectivity_and_Graph_Components|disconnected]], it is a [[Graph_Concepts#Forest|forest]]. | ||
Revision as of 20:37, 9 October 2021
Internal
Overview
A tree is a particular case of a graph.
Free Tree
A free tree is a connected, acyclic, undirected graph.
For an undirected graph G = (V, E), the following statements are equivalent:
- G is a free tree.
- Any two vertices in G are connected by a unique simple path.
- G is connected, but if any edge is removed from E, the resulting graph is disconnected.
- G is connected and │E│ = │V│ - 1.
- G is acyclic and │E│ = │V│ - 1.
- G is acyclic, but if any edge is added to E, the resulting graph contains a cycle.
Forest
If the undirected graph is acyclic, but disconnected, it is a forest.