> For the complete documentation index, see [llms.txt](https://fup1990.gitbook.io/learn/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://fup1990.gitbook.io/learn/shu-ju-jie-gou/b+tree.md).

# B-Tree

B-Tree又叫平衡多路查找树。

![](/files/-LDAno4Ktbxf9hBcqgEc)

## 特性

1. 数据项存储在树叶上
2. 非叶子节点存储直到M-1个关键字以指示搜索的方向
3. 树的根或者一片树叶，或者其儿子数在2和M之间
4. 除根外，所有非树叶节点的儿子数在【M/2】和M之间
5. 所有的树叶都在相同的深度上，并有【L/2】和L之间个数据项

M：M叉树，二叉树则M为二。


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# Agent Instructions
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