my $biscuit = <>;
chomp ($biscuit);

my $count;
my $num = 1;

if ($biscuit == $num){
    print "0\n";
}
else{
    for ($num = 1; $num < $biscuit; $num *= 2){
    $num = $num;
    $count++;
    }
    print "$count\n";

}