#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;

bool has_char(const string& str, const string& source){
    bool has_cha{};
    for(auto x:str){
        auto it = find(source.begin(),source.end(),x);
        if(it!=source.end()){
            has_cha = true;
            break;
        }
    }
    return has_cha;
}

int main() {
    /* Enter your code here. Read input from STDIN. Print output to STDOUT */   
    int n; cin >> n;
    string str; cin >> str;
    string numbers = "0123456789";
    string lower_case = "abcdefghijklmnopqrstuvwxyz";
    string upper_case = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
    string special_characters = "!@#$%^&*()-+";
    int count{};
    bool has_num{}, has_low{}, has_upp{}, has_spe{};
    for(int i=0;i<n;++i){
        if(has_num && has_low && has_upp && has_spe) break;
        if(!has_num) has_num = has_char(str, numbers);
        if(!has_low) has_low = has_char(str, lower_case);
        if(!has_upp) has_upp = has_char(str, upper_case);
        if(!has_spe) has_spe = has_char(str, special_characters);
    }
    if(!has_num) ++count;
    if(!has_low) ++count;
    if(!has_upp) ++count;
    if(!has_spe) ++count;
    if((n+count)<6) count = 6 - n;
    cout << count << '\n';
    return 0;
}