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