tree in graph theory
树
Meaning in context
A tree is a nonempty connected simple graph containing no cycle; this record restricts to finite trees.
本记录中,树是非空、连通且不含圈的有限简单图。
Example
The graph with edges is a tree on four vertices.
Usage and distinctions
A forest need not be connected. A one-vertex graph is a tree even though it has no degree-one leaf.
Read the encyclopedia explanation
Recommended reading in this subject · Preparation & skip guidance
Definition sources
- Keller and Trotter — Applied Combinatorics (2016)Section 5.1, forest/tree definitions and Proposition 5.11 · Checked 2026-10-14
Translation sources
- Reinhard Diestel — 图论,第五版,官方中文目录目录,§1.5「树和森林」(中文名称证据,仅目录) · Checked 2026-10-14