#include<bits/stdc++.h>
using namespace std;

int main()
{
	string special_characters = "!@#$%^&*()-+";
	int n;
	bool d,l,u,sc;
	d = l = u = sc = false;
	string s;
	cin>>n;
	cin>>s;
	for(int i = 0 ; i < n ; i++)
	{
		if(s[i] >= 48 && s[i] <= 57)
		d = true;
		else
		if(s[i] >= 97 && s[i] <= 122)
		l = true;
		else
		if(s[i] >= 65 && s[i] <= 90)
		u = true;
		else
		{
			for(int j = 0 ; j < special_characters.length(); j++)
			if(s[i] == special_characters[j])
			sc = true;
		}
	}
	int ans = 0;
	if(!d)
	{
		ans++;
		n++;
	}
	if(!sc)
	{
		ans++;
		n++;
	}
	if(!l)
	{
		ans++;
		n++;
	}
	if(!u)
	{
		ans++;
		n++;
	}
	ans = ans + max(6-n,0);
	cout<<ans;
	return 0;
}