public static List <string> Str_to_wordList(string str)
{
String_to_words stw = new String_to_words(str, true);
stw.Get_wordHS();
return(stw.word_list);
}
public static HashSet <string> Str_to_wordSet(string str, bool caseSensitive = false)
{
String_to_words stw = new String_to_words(str, caseSensitive);
stw.Get_wordHS();
return(stw.word_hs);
}