Sorry, but this code makes even less sense than your description.

#!/usr/bin/perl

@array_a = (66.93, 66.91, 66.84, 66.82, 66.87, 66.91, 66.7, 66.8, 66.5
+7, 66.61, 66.81, 66.72, 66.78, 66.76, 66.86, 66.73, 66.82, 66.95, 66.
+88, 66.85, 66.87, 66.75, 66.88, 66.93, 66.94, 66.87, 66.88, 66.85, 66
+.83, 66.89, 66.96, 67.03, 67.08, 67.22, 67.36, 67.55, 67.5, 67.49, 67
+.38, 67.49, 67.47, 67.7, 67.62, 67.58, 67.61, 67.79, 67.73, 67.79, 67
+.81, 67.94, 67.99, 68.18, 68.01, 67.82, 67.71, 67.71, 67.65, 67.69, 6
+7.7, 67.7, 67.69, 67.66, 67.62, 67.58, 67.56, 67.5, 67.24, 67.36, 67.
+45, 67.46, 67.38, 67.55, 67.53, 67.56, 67.67, 67.78, 67.78, 67.78, 67
+.78, 67.84, 67.78, 67.74, 67.9, 67.72, 67.74, 67.79, 67.86, 67.88, 67
+.93, 67.97, 68.09, 67.76, 67.89, 67.81, 67.97, 68, 67.84, 67.95, 67.9
+7, 68.02, 68.07, 68.03, 68.08, 68.05, 68.05, 68.07, 68.14, 68.18, 68.
+21, 68.13, 68.07, 68.02, 68, 67.96);

@array_b = (10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 9, 9, 9, 9
+, 9, 9, 9, 9, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10,
+ 10, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 12, 12, 12, 12, 12, 12, 
+10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 9, 9, 9, 9, 9, 9, 8, 8, 8
+, 8, 8, 8, 7, 7, 7, 7, 7, 7, 6, 6, 6, 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7
+, 8, 8, 8, 8, 8, 9, 9, 9, 9, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 
+10, );


(@array_c,@array_d,@array_e) = subroutine(\@array_a,\@array_b);

foreach my $i (0 .. $#array_a) 
{
  print($i, "\t",$array_b[$i],"\t",$array_a[$i],"\t",$array_c[$i],"\t"
+,$array_d[$i],"\t",$array_e[$i],"\n");
}


sub subroutine 
{
  my ($listaref, $listbref) = @_;
  my (@array_a) = @$listaref;
  my (@array_b) = @$listbref;

  foreach my $i (10 .. $#array_a)
  {
    if (( $array_b[$i] >= 5 ) && ( $array_b[$i] < 7 ))
    {
      for ( $l = 1 ; $l <= $array_b[$i] ; $l++ )
      {
        $array_c[$i] = $array_a[$i] + $array_a[$i - $l];
      }
    $array_c[$i] = $array_c[$i] / $array_b[$i];    }
    if (( $array_b[$i] >= 7 ) && ( $array_b[$i] < 9 ))
    {
      for ( $l = 1 ; $l <= $array_b[$i] ; $l++ )
      {
        $array_d[$i]= $array_a[$i] + $array_a[$i - $l];
      }
    $array_d[$i] = $array_d[$i] / $array_b[$i];
    }  
    if (( $array_b[$i] >= 9 ) && ( $array_b[$i] < 15 ))
    {
      for ( $l = 1 ; $l <= $array_b[$i] ; $l++ )
      {
        $array_e[$i]= $array_a[$i] + $array_a[$i - $l];
      }
    $array_e[$i] = $array_e[$i] / $array_b[$i];
    }
  }
  @retval = (@array_c, @array_d, @array_e);
}
__END__
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