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

bool chk(string s,char c){
    int sz = s.size();
    bool ret = false;
    for(int i = 0;i<sz;i++){
        if(s[i] == c){
            ret = true;
            break;
        }
    }
    return ret;
}

int main() {
    string numbers = "0123456789";
    string lower_case = "abcdefghijklmnopqrstuvwxyz";
    string upper_case = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
    string special_characters = "!@#$%^&*()-+";
    int n;
    cin>>n;
    string pass;
    cin>>pass;
    int sz = pass.size();
    bool num,lc,uc,sc;
    num=lc=uc=sc=false;    
    for(int i = 0;i<sz;i++){
        if(chk(numbers,pass[i])){
            num = true;
        }else if(chk(lower_case,pass[i])){
            lc = true;
        }else if(chk(upper_case,pass[i])){
            uc = true;
        }else if(chk(special_characters,pass[i])){
            sc = true;
        }
    }
    int ans = 0;
    if(!num) ans++;
    if(!lc) ans++;
    if(!uc) ans++;
    if(!sc) ans++;
    if(ans+sz<6) ans = ans + (6-(ans+sz));
    printf("%d\n",ans);
    return 0;
}