Under this command, the program would open and read each of the input files in turn, building up a binary tree of words and counts as it progresses. Once all files have been read and closed, it must create the output file and write out the words in the tree in alphabetical order, one word per line, along with the number of occurrences of that word. Your program should ignore the case of the words, so that -This? and -this? are considered the same. However, words that are actually spelled differently - such as -car? and -cars? - are considered to be different words