The text file words.txt , which is included in the source code for this book, contains an alphabetically sorted list of English words. Note that the words are in mixed upper and lowercase.

Write a program that reads this file and finds the longest word that reverses to a different word. For example, “stun” reverses to make the word “nuts” but is only four letters long. Find the longest such word. In writing your program you can use the information that the words.txt file contains exactly 45,407 words.

Depending on the speed of your computer and your implementation, execution of this program may take from minutes to hours.