Reverse Levenshtein distance
问题 In levenshtein distance you ask the question, given these two strings, what is their levenshtein distance. How would you go about taking a string and a levenshtein distance and generating all the strings within that levenshtein distance. (It would also take in a character set). So if i pass in a string x and a distance d. then it would give me all the strings within that edit distance, including d-1 and d-2....d-n; (n < d). Expected functionality: >>> getWithinDistance('apple',2,{'a','b',' '}