Answers to Part 2 Exercises
       
       Solution to "EXPORT" Problem
       
         Typing:
         
           1 ; ?EXPORT? delete
         
         will do it.  By starting from the first line in the file and
         searching backwards, you guarantee the the first line to be
         searched will be the last line of the file (due to wraparound),
         then the second-to-last line, etcetera.  As soon as the editor
         finds a match it stops, so there cannot be another "EXPORT" lower
         down in the file.
         
         
         Solution to First-Line Problem
         
         This requires two commands:
         
           $ print
           /EXPORT/ delete
         
         The first command prints the last line in the file, which is not
         helpful in itself, but also leaves that last line as the current
         line. Then, the address of the second command causes a forward
         search and, due to wraparound, the search must begin with the
         file's first line.
       
       
       Solution to Noninclusive Problem
       
         Just add a plus sign after the address before the comma, and a
         minus sign to the address after it, like this:
         
           ?abc? + , /xyz/ -
         
         Each of these offsets moves one line toward the center of the text
         section the combined address specifies, so each has the effect of
         leaving out the line where the match was found.  (That the first
         search was backward and the second forward is not relevant.  The
         point is that the address before the comma, whatever it is,
         receives the plus offset, while the address after the comma gets
         the minus offset.)
       
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