The device for converting series of {HEAD ~ A input data elements} to {TAIL ~ series} of A output data elements comprises a memory means for containing these series of input and output data elements 
The device for converting series of { HEAD ~ A input data elements } to { TAIL ~ series } of A output data elements comprises a memory means for containing these series of input and output data elements
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH