A bar code scanner in {TAIL ~ the second sorting pass} scans bar codes of {HEAD ~ each printed bar code} and decodes said bar code 
A bar code scanner in { TAIL ~ the second sorting pass } scans bar codes of { HEAD ~ each printed bar code } and decodes said bar code
OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH