use WWW::Mechanize;
    my $m = WWW::Mechanize->new( autocheck => 1 );
$m->get("https://www.bittorrent.com/account/signin");
$mech->submit_form(
           form_name => 3,  #I don't know what is this simply i gave
           fields      => {
           username => "abcd",
           password => "abcd",
                },
               button    => 'Sign In',
     );

##</code><code>##

use WWW::Mechanize;
use HTTP::Cookies;
my $outfile = "Result.htm";
my $url = "https://www.bittorrent.com/account/signin";
my $username = "abcd";
my $password = "abcd";
my $cookiefile = 'cookies.txt';
my $cookie_jar = HTTP::Cookies->new(File => $cookiefile, autosave =>1);
my $mech = WWW::Mechanize->new();
$mech->cookie_jar($cookie_jar);
$mech->get($url);
print "form submit failed!", $mech->response->status_line, "\n" unless $mech->success;
$mech->set_visible( $username );
$mech->click_button(value => "Sign In");

##</code><code>##

use WWW::Mechanize;
use URI::URL;
use LWP::Simple;

        $url="https://www.bittorrent.com/account/signin";
        $m=WWW::Mechanize->new();
        $m->get($url);
        $content=$m->content;

        open(FD,">>html");
        print FD "$content\n";

        $username="shekar";
        $password="shekar";
        $m->set_visible($username,$password);
        $m->submit();