#!/usr/bin/perl -w
# addpp: add pre and post tags to ner data
# usage: addpp < file
# 20060220 erikt@science.uva.nl

$command = $0;
while (<STDIN>) {
   $line = $_;
   chomp($line);
   $line =~ s/^\s+//;
   if ($line eq "") { $tag = ""; }
   else {
      if ($line !~ /\s/) { die "$command: cannot happen: found line $line\n"; }
      @w = split(/\s+/,$line);
      $tag = pop(@w);
      $words = join(" ",@w);
      if (defined $lastTag and $lastTag eq "O" and $tag ne "O") {
         $lastTag = "PRE$tag";
      }
      if (defined $lastTag and $lastTag ne "" and $lastTag ne "O" and 
          $lastTag !~ /^POST/ and $tag eq "O") {
         $tag = "POST$lastTag";
      }
   }
   if (defined $lastTag) {
      if ($lastTag ne "") { print "$lastWords $lastTag"; }
      print "\n";
   }
   $lastTag = $tag;
   $lastWords = $words;
}
if (defined $lastTag) {
   if ($lastTag ne "") { print "$words $lastTag"; }
   print "\n";
}

exit(0);

