See if substr will do what you want.

smartperl:

When I see a problem like this, I normally break it apart into steps. Then, if I can't immediately write down the solution to any of those steps, I break the steps down even further. Something like:

my $spec="11-29,39-72,99-100,103,107";
my $input = "The quick red fox jumped over the lazy brown dog.";
# break spec into set of offsets and lengths

# for each offset and length...
for (my $idx=0 .. $#specs) {
   my ($input, $offset) = # how did I store them?

   #...extract a substring...
   my $substring = substr($input, $offset, $length);

   #...then print the result
   print "<$substring> is substr(...,$offset,$length)\n";
}
[download]

Ok, I handled the easy part. Now I break down each comment that doesn't have code. Keep doing that until everything is done.

When you start out, you sometimes get a problem that seems complicated, but if you start breaking it down into subproblems, you often find that it's just a few trivial bits glued together.

...roboticus

When your only tool is a hammer, all problems look like your thumb.

This sound like a home work, you should show us what did you try before

#!/usr/bin/perl
use strict;
use warnings;

my $range="0-2,6-10,13,15";
my $test="this is a test with more than 15 characters";

for my $r (split (",",$range))
{
    if ($r =~ /^(\d+)(-(\d+))?$/)
    {
        my $first=$1;
        my $length=1;
        if (defined ($3))
        {
            $length=$3-$1+1;
        }

        print "$r - ", substr ($test, $first,$length),"\n";
    }
}
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#!/usr/bin/perl
use strict;
use warnings;

my $range="0-2,6-10,13,15";
my @range=split(",",$range);
my $test="this is a test with more than 15 characters";

my $last=0;
my $regex="";
for (@range)
{
    if (/^(\d+)(-(\d+))?$/)
    {
        my $first=$1;
        my $length=1;

        if ($last lt $first)
        {
            $regex.="."x($last-$first);
        }
        $last=$first;
        if (defined ($3))
        {
            $length=$3-$1+1; $last=$3;
        }
        $regex.="(".("."x$length).")";
    }
}

my @matches = $test =~ /$regex/;

my $n=0;
for (@matches)
{
    print ++$n." ($range[$n-1]): \"" ."$_","\"\n";
}
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main::(-e:1):   42
  DB<1> $input = "The quick red fox jumped over the lazy brown dog.";

  DB<2> $spec = "3-6,9-13,17-20";

  DB<3> $spec =~ s/\-/../g;

  DB<4> @in = split //, $input;

  DB<5>  print "@in";
T h e   q u i c k   r e d   f o x   j u m p e d   o v e r   t h e   l 
+a z y   b r o w n   d o g .
  DB<6> print  @in[eval ($spec)];
 qui red  jum
  DB<7>
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Now, of course, since array subscripts start at 0, I am counting the letters from 0. If we need counting letters from 1, not 0, we can just add an empty element at the beginning of the array:

  DB<7> unshift @in, "";

  DB<8> print  @in[eval ($spec)];
e quk redx ju
[download]

Thank you geeks for your support. I could sort it out in a way similar to what i5513 demonstrated. Thank you all... Looking forward to extended support