19. The method of claim 13 wherein said storing step comprises storing said strings in said storage means in a linked tree structure, said stream of data characters including a repeating character string comprised of a repeating character, said method compressing said repeating character string in two compressed codes irrespective of the length thereof.
19. The method of claim 13 wherein said storing step comprises storing said strings in said storage means in a linked tree structure, said stream of data characters including a repeating character string comprised of a repeating character, said method compressing said repeating character string in two compressed codes irrespective of the length thereof. 20. The method of claim 19 wherein said previous longest matched string comprises said repeating character, said searching step includes matching said repeating character string on a path through said tree, and said entering step includes entering said extended strings on said path, thereby compressing said repeating character string in two compressed codes irrespective of the length thereof.