use Data::Dumper;

my $tpl = ['A -4 B','B -4 C','C -4 A','A -4 B'];
get_alphb_fr_tpl($tpl);

sub get_alphb_fr_tpl
{
  my $aref = shift;
  my @str  = grep (!/[\d+\s+]/,map{ split " ",$_} @{$aref}) ;
  print Dumper \@str ;
  return;
}