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