Write a C++ program that will the binary search tree implementation of a dictionary to find Word co-occurrence (appearing together in sequence or simultaneously). This is a phenomenon that counts the frequency of pairs of words. Your code should insert as a pair any two words and keep track of their frequency.

For example, if your input file contains the following sentence

a penny saved is a penny earned

the following will happen

add : frequency 1

add frequency 1

add frequency 1

add frequency 1

in tree only add frequency becomes 2

Add frequency 1

Etc.

Your program should:

read text from an input file.

Calculate statistics and display results including the pair and its frequency.