<?php
error_reporting(0);
define('M', 1000000007);
define('V', count($argv) - 1);
function vprint($x)
{
	if(!V)
		return;
	if(is_array($x))
		print_r($x);
	else
		print($x);
}

$f = fopen ("php://stdin","r");
fscanf($f,"%d",$len);
	$s = fgets($f);

$aa = array("0123456789", "abcdefghijklmnopqrstuvwxyz", "ABCDEFGHIJKLMNOPQRSTUVWXYZ", '!@#$%^&*()-+');
$ss = str_split($s);

$cadd = 0;
foreach($aa as $n => $a)
{
	foreach($ss as $x)
	{
		if(strstr($a, $x))
		{
			$nn[$n] = 1;
			break;
		}
	}
}


foreach($aa as $n => $a)
{
	if(!isset($nn[$n]))
		$cadd ++;
}
vprint("$cadd\n");

$ladd = 6 - $len - $cadd;
if($ladd > 0)
	$cadd += $ladd;
echo "$cadd\n";