use strict;
 
my @AoA=(
      ['A','B','C'],
      ['A','D','C'],
      ['A','B','C'],
     );
 
my (%join,@AoH);
 
for (@AoA) {
  @join{@$_}=();
  my %set;
  @set{@$_}=(); 
  push @AoH,\%set;  
}
 
for my $elem (sort keys %join) {
  for (@AoH){
    print "$elem" if exists $_->{$elem};
    print "\t";
  }
  print "\n";
}