Appropriate registers are provided to store the numbers which represent the subtrahend and {HEAD ~ minuend} of {TAIL ~ a subtraction operation} 
of
Appropriate registers are provided to store the numbers which represent the subtrahend and { HEAD ~ minuend } of { TAIL ~ a subtraction operation }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL