The program takes as {TAIL ~ input} an initial data set that contains probabilistic information and returns as {HEAD ~ output} a sequence of elementary operations  
The program takes as { TAIL ~ input } an initial data set that contains probabilistic information and returns as { HEAD ~ output } a sequence of elementary operations
OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH