my $findline = 13;
 for ($i=$Drop; $i<=$Last; $i++){
      print TIMEFILE1 "Drop $i\n";

      for ($k=1; $k<=$KTM;$k++){
      
          $String1= "RK" . "$i" . "$suf[$k-1]";

          $file = $String1;

          if (-e $file){

              open (F, $file) || ("Could not open $file!");
              $lines++ while (<F>);
              close (F);

              open (F, $file) || ("Could not open $file!");
              while ($line = <F>)
              {
                   if ($. == $findline){
                   ($field1, $field2, $field3, $field4) = split ',', $line;
                   print TIMEFILE1 "$field2 : $field3 : $field4 \t";
              }
              if ($. == $lines){
                   ($field1, $field2, $field3, $field4) = split ',', $line;
                   print TIMEFILE1 "$field2 : $field3 : $field4 \t $String1\n";
              }
          }
          $lines = 0;
          close (F);
      }
   }
}