#include <bits/stdc++.h>

using namespace std;

int minimumNumber(int n, string pass) {
    
    int i=1;
    char t;
    int a =0,b=0,c=0,d=0;
    t = pass[0];
    while(t!='\0')
    {
        if( t>=48 && t<=57 )
            a=1;
        if( t>=65 && t<=90 )
            b=1;
        if( t>=97 && t<=122 )
            c=1;
        if( t=='!' || t=='@' || t=='#' || t=='$' || t=='%' || t=='^' || t=='&' || t=='*' || t=='(' || t==')' || t=='-' || t=='+')
            d=1;
        
        t = pass[i];
        i++;
    }
    i--;
    int res=0;
    if(a==0)
    {
        res++;
        i++;
   }
    if(b==0)
    {
        res++;
        i++;
   }
    if(c==0)
    {
        res++;
        i++;
   }
    if(d==0)
    {
        res++;
        i++;
   }
        
    
    if(i<6)
    {
        res = res+6-i;
    }
    
    
    
    return res;
}

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