"Third week of data structure" tree knowledge point finishing (top)

1, the definition of the tree

Tree: A finite set of n (n>=0) nodes

Sub-trees are disjoint.

In addition to the root node, each node has and has only one parent node.

A tree of N nodes has a N-1 edge.

2. Some basic terms of the tree

(1) node degree (degree): Number of sub-trees of nodes

(2) The degree of the tree: the maximum number of degrees in all nodes of the tree

(3) Leaf junction (leaf): nodes with a degree of 0

(4) Parent node: A node with a subtree is the parent node of the root node of its child tree

(5) Sub-node (child): If the A node is the parent node of the b node, then the B node is the Sub-node of Node A.

(6) Sibling node (Sibling): Each node with the same parent node is a sibling node.

(7) path and path length: The path from node N1 to NK is a node sequence. The number of edges that the path contains is the length of the path

(8) Ancestor node (Ancestor): All nodes along the tree root to a node path are the ancestor nodes of this node.

(9) Descendants node (descendant): All nodes in a subtree of a node are descendants of this node

(10) node hierarchy (level): Specifies that the root node is at 1 levels, and that the number of layers of any other node is the layer of its parent and 1

(11) Depth of tree (Depth): The maximum level of all nodes in the tree is the depth of this tree

3. Binary tree and storage structure

(1) Definition

A binary tree is an ordered tree with a maximum of two subtrees per node.

Specific five basic forms

Special two-fork tree

(2) Several important properties of binary tree

(2) Sequential storage structure of binary tree

A typical two-fork tree is a waste of space if stored in this way.

(3) Chain storage structure of binary tree

"Third week of data structure" tree knowledge point finishing (top)