Binary Search Trees

Let every node of a binary tree be associated with a key value. A binary search tree is a tree in which every node of the tree obeys the relationship: the values of each key found in the left subtree for a given node are less than or equal to the value of the key in the node and the values of each key in the right subtree are greater than the value of the key of that node. Scanning the leaf nodes of a binary search tree from left to right results in an increasing sequence according to the key values.