Write a spell checker class that stores a set of words, W, in a hash table and implements a function, spellCheck(s), which performs a Spell Check on the string s with respect to the set of words, W. If s is in W, then the call to spellCheck(s) returns an iterable collection that contains only s, since it is assumed to be spelled correctly in this case. Otherwise, if s is not in W, then the call to spellCheck(s) returns a list of every word in W that could be a correct spelling of s. Your program should be able to handle all the common ways that s might be a misspelling of a word in W, including swapping adjacent characters in a word, inserting a single character inbetween two adjacent characters in a word, deleting a single character from a word, and replacing a character in a word with another character. for an extra challenge, consider phonetic substitutions as well.
