For this assignment you are going to build a variation of the information 
retrieval program described in your text book. However, the program in 
the book uses just binary search trees and we would like you to build 
two different structures, a binary search tree and an AVL tree and to 
compute some statistics for insertion and searching these two structures. 

Input 

The first input to your program will be the name of a file that contains 
some number of words as defined in the text. You will read in the file 
and insert each word into both structures, binary search tree and AVL tree. 
After inserting, you will go into an input mode where you 
repeated read in instructions until you read in the exit instruction. 
The instructions will be one of four types.