while (<MYFILE>)
{
  $alldata .= $_ ;

  if(/(\S+)\s+(\d+)/)
  {
    $mylist{$1} = {value => $2, linenum => $. };
  }
}

##</code><code>##

for my $key ( keys %mylist )
{
  my $value   = $mylist{$key}{value};
  my $linenum = $mylist{$key}{linenum};

  print "$key has value $value, found on line $linenum\n";
}