use v5.010;
use strict;
use warnings;

# Reading in file in raw format.
local $/;
open F, "<:raw", "input.pdf" or die $!;
my $raw_content = <F>;

my $nr_of_cos_objects = 10;
my @counter = (1..$nr_of_cos_objects);
my $position = 0;

for my $number (@counter) {
    my $result = $raw_content=~qr/^${number} 0 obj/aa;
    if ($result) {
        say "Object item [$number] ('${number} 0 obj') starts at position  [$-[0]]";
    } else {
        say "Object item [$number] ('${number} 0 obj') start position not found";
    }

    if ($result) {
        say "Object item [$number] ('${number} 0 obj') ends   at position  [$+[0]]\n";
    } else {
        say "Object item [$number] ('${number} 0 obj') end   position not found\n";
    }
}

say "End test program.  Bye...";