This Prolog library provides predicates for handling binary trees. Binary trees are represented as nil (the empty tree) or as t(L, X, R), where L and R are left and right subtrees. The values in binary trees can be numbers or letters. For binary search trees, the values must be integers.

1. Download the file binary_trees_library.pl.
2. Load the file into Prolog either in your code or in your interpreter with the following command use_module('path/to/binary_tree_library.pl').
3. Use the predicates.

Below are all the predicates I implemented for the library. You will find a more detailed usage with code snippets in the binary_tree_library.pl file.

• Returns the height H of the binary tree T.

• Succeeds if predicate P is true for every value in the tree T.

• Performs a right fold of a predicate over all values in a tree.

• Flattens a tree T, producing a list of values L.

• Counts all nodes in a tree.

• Counts the number of leaves in the binary tree T.

• Searches for a specified element X in a binary tree T.

• Performs a preorder traversal of a binary tree T.

• Performs an in-order traversal of a binary tree T.

• Performs a postorder traversal of a binary tree T.

• Gives a list Result containing all nodes of depth D in a binary tree T.

• Gives the depth D of a node of value V in a binary tree T.

• Returns true if the node of value V is a leaf of the binary tree T.

• Returns true if the binary tree T is full.

• Returns true if the binary tree T is perfect.

• Returns true if the binary tree T is quasi-perfect.

• Returns true if the binary tree T is a binary search tree.

• Searches for a specified element X in a binary search tree T.

• Inserts a value X into a binary search tree T, producing a tree T1.

• Deletes a specified element X from a binary search tree T, producing a tree T1.

• Finds the maximum value Max in the binary search tree T.

• Finds the minimum value Min in the binary search tree T.

Here are some examples of trees that I have used to test the code:

• my_bst1(T) - Binary search tree with integer values.
• my_btree(T) - Binary tree with non-integer values.
• my_full_tree(T) - Full binary tree.
• my_perfect_tree(T) - Perfect binary tree (also a binary search tree).
• my_quasi_perfect_tree(T) - Quasi-perfect binary tree (also a binary search tree).
• my_alphabet_tree(T) - Binary tree with alphabet letters.

Example usage:

?- my_full_tree(_T), is_full(_T).

This library is released under the MIT License (see more information about it in file LICENSE).