19. The decoding method of claim 17 , wherein the step of selecting one of the encoding sequence combinations is repeated to select a plurality of the encoding sequence combinations such that the selected encoding sequence combinations are mapped into a plurality of output sequences according to the mapping.
17. A decoding method comprising the steps of: maintaining a mapping that maps a plurality of encoding sequences, each of which includes at least one encoding symbol chosen from an encoding symbol set, to a plurality of decoding sequences, each of which includes at least one decoding symbol chosen from a decoding symbol set which is used by non-logographic languages; receiving encoding symbol or symbols into an input sequence; generating a plurality of encoding sequence combinations if the length of the input sequence is greater than one; selecting one of the encoding sequence combinations; mapping the selected encoding sequence combination into an output sequence according to the mapping; outputting the output sequence.