#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
#include <list>
#include <stack>
#include <limits.h>
#include <iomanip>
#include <stdint.h>
#include <string>
#include <stdio.h>  
#include <stdlib.h>

using namespace std;

int main(){

	int num=0,lower=0,upper=0,special=0;

	int N;
	string inp;
	cin>>N>>inp;

	int res = 0;
	int l = N;

	string spc = "!@#$%^&*()-+";

	for (int i = 0; i < N; ++i)
	{
		if (spc.find(inp[i])!=string::npos)
		{
			special = 1; 
			// cout<<"spc"<<endl;
		}
		else if ((0 <= (inp[i]-'0'))&&((inp[i]-'0') <= 9))
		{
			num = 1;
			// cout<<"num"<<endl;
		}
		else if ((0 <= (inp[i]-'A'))&&((inp[i]-'A') <= 25))
		{
			upper = 1;
			// cout<<"upp"<<endl;
		}

		else if ((0 <= (inp[i]-'a'))&&((inp[i]-'a') <= 25))
		{
			lower = 1;
			// cout<<"lower"<<endl;
		}
	}

	if (!lower)
	{
		res++;
		l++;
	}
	if (!upper)
	{
		res++;
		l++;
	}
	if (!num)
	{
		res++;
		l++;
	}
	if (!special)
	{
		res++;
		l++;
	}
	if (l < 6)
	{
		res += (6 - l);
	}

	cout<<res<<endl;
}