#!/bin/perl
use strict;
use warnings;
 
my $filename = '808.nc';
open(my $fh, '<:encoding(UTF-8)', $filename)
  or die "Could not open file '$filename' $!";
my $g="G";
my $f="F";
while (my $row = <$fh>) {
  chomp $row;
  my @words = split / /, $row;
    foreach (@words){
    my $Word=$_;
    my $char=substr($_, 0, 1);
     if ($char eq "G"){
      if($Word ne $g){
      $g=$Word;
      print "$Word "
      }
     }    
     elsif ($char eq "F"){
      if($Word ne $f){
      $f=$Word;
      print "$Word "
      }
     }    
     else {print "$Word "}
    }
  print "\n";
}