Faster Computation of Levenshtein Distance for Spell Checkers

Fast String Comparator is an efficient algorithm for computating Levenshtein distance up to two. Given two strings of length m and n (m <= n), the computation requires O(1) space and O(n) time, which is much smaller and faster than well-known Wagner-Fisher algorithm.

It is mainly targeted at the use in spell checkers, where considering words within two edit distance suffices.