In computer science, a binary search tree (BST), sometimes also called an
ordered or sorted binary tree, is a node-based binary tree data structure
which has the following properties:[1]
The left subtree of a node contains only nodes with keys less than the node'
s key.
The right subtree of a node contains only nodes with keys greater than the
node's key.
The left and right subtree must each also be a binary search tree.
There must be no duplicate nodes.
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