{
  "aesG gly4" => 2,
  "aesG phil" => 2,
  "aesG tomD" => 2,
  "gly4 phil" => 2,
  "gly4 tomD" => 3,
  "phil tomD" => 2,
}

##</code><code>##

use Data::Dump "pp";
my %count;
 
 
while(<DATA>) {
  chomp;
  @keys= sort split;
  for my $a (0..$#keys){
    for my $b ($a+1.. $#keys) {
#     pp [$keys[$a],$keys[$b]];
      $count{$keys[$a],$keys[$b]}++
    }
  }
  
}
 
pp \%count;
 
__DATA__
tomD gly4 phil
aesG tomD gly4 phil
aesG phil
aesG tomD gly4

##</code><code>##

{
  "aesG\34gly4" => 2,
  "aesG\34phil" => 2,
  "aesG\34tomD" => 2,
  "gly4\34phil" => 2,
  "gly4\34tomD" => 3,
  "phil\34tomD" => 2,
}