#!/usr/bin/perl
use strict;
use diagnostics;
use 5.010;
use Path::Tiny qw/ path /;

my $raw   = path("sample.vcd")->slurp_raw;
my $re = qr{ 
\$end
\$dumpoff \$end
[\r\n ]+
(\#[\d]+)
[\r\n ]+
\$dumpon \$end
[\r\n ]+
(.*?)
\#[\d]+
}sx;

while( $raw =~ m/$re/g ){
    my( $id, $tidy ) = ( $1, $2 );
    say $1; 
    say $2; 
        }