What is a binary tree

A binary tree is a hierarchical data structure. A binary tree consists of nodes, each node has:

A left node
A right node
A data element, which could be of any type

Here's how a typical binary tree looks:

    public class Node
    {
        public int Value;
        public Node Left;
        public Node Right;

        public Node(int value)
        {
            Value = value;
        }
    }

A binary tree can be represented graphically

binary tree

Terminology used in trees:

Root: the node at the top of the binary tree
Child: a node below a given node
Parent: the converse definition of a child (the opposite of child)
Leaf: a node without child nodes
Edge: a connection between two nodes
Subtree: a tree representing the descendants of a node
Level: the level at which a node resides, its generation

binary tree

Another two definitions are:

Depth: the number of edges from the root to the node
Height: the number of edges from the node to the deepest leaf

binary tree

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