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Practice

What is a Tree?

A tree is a hierarchical data structure consisting of nodes, where each node points to its child nodes.

Trees are used to represent hierarchical data structures and can be found in various applications like file systems, organizational charts, and DOM (Document Object Model).


Key Elements of a Tree​

  1. Node:

    • The basic unit of a tree, which contains data and references to other nodes (typically child nodes).

    • Example: Files or folders in a file system, employees in an organizational chart

  2. Root Node:

    • The topmost node in the tree structure.

    • This node has no parent and serves as the starting point of the tree.

  3. Child Node:

    • Nodes derived from another node (parent node).

    • A single parent node can have multiple child nodes.

  4. Parent Node:

    • A node that has one or more child nodes.

  5. Sibling Nodes:

    • Nodes that share the same parent node.

  6. Leaf Node / Terminal Node:

    • A node with no child nodes.

    • Located at the lowest level of the tree.

  7. Subtree:

    • A part of the tree consisting of a node and its descendant nodes.

  8. Depth:

    • Distance from the root node to a specific node.

  9. Height:

    • The depth of the deepest node in the tree.

Implementing in Python​

The basic way to implement a tree is by using classes and objects. Each node is represented as an object and includes references to its child nodes.

  1. Node Class:

    • Stores data and references to child nodes.

  2. Tree Creation and Traversal:

    • Starts from the root node, nodes are added as needed, and the tree is traversed based on the chosen method.

The implementation of a tree can vary depending on the type and purpose of the tree. For instance, a Binary Search Tree is specialized for inserting, deleting, and searching data, while a Balanced Tree is used to optimize search time.

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