Define a tree in the context of data structures.

Define a tree in the context of data structures.

A tree is a hierarchical structure that consists of nodes, with a single node designated as the root. The tree data structure is defined by the following properties:

1. Root: The topmost node in the tree. The tree originates from this node, and it has no parent.
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3. Nodes: Each element in the tree is called a node. A node contains a value or data and links to its children.
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5. Edges: The connections between nodes are called edges. An edge connects a parent node to a child node.
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7. Parent and Child: A parent node is a node that has one or more children. A child node is a node that has a parent.
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9. Subtree: A subtree is a portion of the tree that includes a node and all of its descendants.
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11. Leaf Node: A node that has no children. It is also called a terminal or external node.
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13. Internal Node: A node that has one or more children. It is also called a non-terminal node.
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15. Level/Depth: The level of a node is determined by the number of edges from the root to the node. The root is at level 0, its children are at level 1, and so on.
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17. Height: The height of a node is the number of edges on the longest path from the node to a leaf. The height of the tree is the height of the root node.
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19. Degree: The degree of a node is the number of children it has. The degree of the tree is the maximum degree of any node in the tree.