#include <bits/stdc++.h>

using namespace std;
string numbers = "0123456789";
string lower_case = "abcdefghijklmnopqrstuvwxyz";
string upper_case = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
string special_characters = "!@#$%^&*()-+";
int n;
int main() {
    /* Enter your code here. Read input from STDIN. Print output to STDOUT */
  cin >> n;
  string s;
  cin >> s;
  int ret = 0;
  
  // check digit
  bool has1 = false;
  for(auto c: numbers) {
    if (s.find(c) != -1) {
      has1 = true;
      break;
    }
  }
  
  if (has1 == false) ret += 1;
  
  // check lowercase
  bool has2 = false;
  for(auto c: lower_case) {
    if (s.find(c) != -1) {
      has2 = true;
      break;
    }
  }
  
  if (has2 == false) ret += 1;
  
   // check uppercase
  bool has3 = false;
  for(auto c: upper_case) {
    if (s.find(c) != -1) {
      has3 = true;
      break;
    }
  }
  
  if (has3 == false) ret += 1;

  
  // check special
  bool has4 = false;
  for(auto c: special_characters) {
    if (s.find(c) != -1) {
      has4 = true;
      break;
    }
  }
  
  if (has4 == false) ret += 1;
  
  if (s.size() + ret < 6) ret += 6 - s.size() - ret;
  cout << ret << endl;
  return 0;
}