#include <bits/stdc++.h>

using namespace std;

int minimumNumber(int n, string pass) {
   
    int no = 0 , lc = 0 , uc = 0 , sc = 0, req = 0;
    for(int i = 0 ; i < n ; i++){
        if(pass[i]>='0' && pass[i]<='9'){
            no ++;
        }
        else if(pass[i]>='a' && pass[i]<='z'){
            lc ++ ;
        }
        else if(pass[i]>='A' && pass[i]<='Z'){
            uc ++ ;
        }
        else if(pass[i]=='!'||pass[i]=='@'||pass[i]=='#'||pass[i]=='$'||pass[i]=='%'||pass[i]=='^'||pass[i]=='&'||pass[i]=='*'||pass[i]=='('||pass[i]==')'||pass[i]=='-'||pass[i]=='+'){
            sc ++;
        }
    }
    if(no == 0){
        req ++;
    }
    if(lc == 0){
        req ++ ;
    }
    if(sc == 0){
        req ++;
    }
    if(uc == 0){
        req ++;
    }
    if(n+req<6){
        req+=(6-n-req);
    }
    return req;
    
}

int main() {
    int n;
    cin >> n;
    string password;
    cin >> password;
    int answer = minimumNumber(n, password);
    cout << answer << endl;
    return 0;
}