#include <bits/stdc++.h>

using namespace std;

int minimumNumber(int n, string password) {
    // Return the minimum number of characters to make the password strong
  string  numbers = "0123456789";
  string  lower_case = "abcdefghijklmnopqrstuvwxyz";
  string  upper_case = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
  string  special_characters = "!@#$%^&*()-+";
  int ans=4,cnt=0;  
  for(int j=0;j<numbers.size();j++)  
  {
      int f=0;
      for(int i=0;i<n;i++)
      {
          if(numbers[j]==password[i])
          {
              cnt++;
              f=1;
              break;
          }
      }
      if(f==1)
          break;
  }
   for(int j=0;j<lower_case.size();j++)  
  {
      int f=0;
      for(int i=0;i<n;i++)
      {
          if(lower_case[j]==password[i])
          {
              cnt++;
              f=1;
              break;
          }
      }
      if(f==1)
          break;
  }  
   for(int j=0;j<upper_case.size();j++)  
  {
      int f=0;
      for(int i=0;i<n;i++)
      {
          if(upper_case[j]==password[i])
          {
              cnt++;
              f=1;
              break;
          }
      }
      if(f==1)
          break;
  }  
   for(int j=0;j<special_characters.size();j++)  
  {
      int f=0;
      for(int i=0;i<n;i++)
      {
          if(special_characters[j]==password[i])
          {
              cnt++;
              f=1;
              break;
          }
      }
      if(f==1)
          break;
  }  
  ans= (ans-cnt);
  //  cout<<ans<<endl;
  if(password.size()<6)
  {
      n=(6-n);
      n=n-ans;
      n=max(0,n);  
      ans=ans+n;
  }
 

  return ans;  
}

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