3. The method of claim 2 , wherein the set of substrings comprises a set of alphabetic letters which is used to write one or more natural languages.
3. The method of claim 2 , wherein the set of substrings comprises a set of alphabetic letters which is used to write one or more natural languages. 4. The method of claim 3 , wherein the substrings in the set of substrings further comprise a space character, a comma character, a period character, an apostrophe character, and an unknown character.