Word-Count-Dictionary-B-Tree

A Dictionary with the following features:

1. Insert word
2. Delete a word
3. Print words in a lexicographic order
4. Print First and Last word as per lexicographic order
5. Print Least Occurring Words
6. Print Words occurring more than k (user provided) times
7. Print word and their counts in a range (user provided lower bound and upper bound).
8. Write the dictionary to a Dictionary.txt on Exit. The file serves as the base dictionary for further executions and above operations.