import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
class p1 {
    public static void main(String args[])throws IOException {
        BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
        StringBuilder output=new StringBuilder();

        int N=Integer.parseInt(br.readLine());
        String pass=br.readLine();
        boolean len=false,digit=false,lower=false,upper=false,special=false;

        if(N>=6)
            len=true;
        for (int i = 0; i <N ; i++) {
            char c=pass.charAt(i);
            if(c>='0' && c<='9')
                digit=true;
            else if(c>='a' && c<='z')
                lower=true;
            else if(c>='A' && c<='Z')
                upper=true;
            else if(c=='!'|| c=='@' || c=='#' ||c=='$' ||c=='%' ||c=='^' || c=='&' || c=='*' || c=='(' || c==')' || c=='-' || c=='+' )
                special=true;
        }

        int count=0;
        if(!digit)
            count++;
        if(!lower)
            count++;
        if(!upper)
            count++;
        if(!special)
            count++;

        if(N+count<6) {
            //System.out.println("inside");
            count+=6-(N+count);
        }

        System.out.println(count);
    }
}