#include <bits/stdc++.h>

using namespace std;

int minimumNumber(int n, string pass) {
    bool l=false,u=false,d=false,s=false;
    char special;
    for(int i =0; i < pass.size(); i++){
            if( islower(pass[i]) )
                l = true;

            if( isupper(pass[i]) )
                u = true;

            if( isdigit(pass[i]) )
                d = true;

            special = pass.find_first_not_of("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890 ");

            if (special != string::npos)
                s = true;
    }
    int cnt=0;
    if(l==false){
        cnt++;
        n++;
    }
    if(u==false){
        cnt++;
        n++;
    }
    if(d==false){
        cnt++;
        n++;
    }
    if(s==false){
        cnt++;
        n++;
    }
    if(n<6){
        cnt+=(6-n);
    }
    return cnt;
}

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