or less magical 
my @data = ...

xadd( \@data, "3.4", 1);

sub xadd
{
  my $data = shift;
  my $elem = shift;
  my $incr = shift || 1;

  for ( 0..$#{$data} )
  {
    $data->[1]->[$_] += $incr,
    $i = 1,
    last
      if $data->[0]->[$_] eq $elem;
  }
  
  unless ( $i )
  {
    push @{$data->[0]}, $elem;
    push @{$data->[1]}, $incr;
    $data->[2] = [ sort { $a <=> $b } @{$data->[1]};
  }

  # comment this line out if you don't 
  # need to re-sort the 3rd array
  $data->[2] = [ sort { $a <=> $b } @{$data->[1]};

}

[download]
Update: After posting I read that the OP needs that the solution works with an empty array. I added the edge case.


holli, /regexed monk/

In reply to Re^4: Converting a growing hash into an array of arrays by holli
in thread Converting a growing hash into an array of arrays by madbombX

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