#include <bits/stdc++.h>
#define MOD 1000000000
#define ll long long
#define MAX 100000
#define SIZE 5
using namespace std;

int main(){

  int i, n, digit = 0, special = 0, upper = 0, lower = 0, ans = 0, len = 0;

  cin >> n;

  string s;

  cin >> s;

    for(i = 0;i < n; ++i){

      if(s[i] >= 'A' && s[i] <= 'Z') ++upper;
      else if(s[i] >= 'a' && s[i] <= 'z') ++lower;
      else if(s[i] >= '0' && s[i] <= '9') ++digit;
      else if(s[i] == '!' || s[i] == '@' || s[i] == '#' || s[i] == '$' || s[i] == '%' || s[i] == '^' || s[i] == '&' || s[i] == '*' || s[i] == '(' || s[i] == ')' || s[i] == '-' || s[i] == '+') ++special;
    }
    len = upper + lower + digit + special;
    if(upper < 1) {ans += 1; len += 1;}
    if(lower < 1) {ans += 1; len += 1;}
    if(digit < 1) {ans += 1; len += 1;}
    if(special < 1) {ans += 1; len += 1;}
   
   if(len > 6) cout << ans;
  else cout << ans + 6 - len;

 return 0;

}