#include "bits/stdc++.h"
using namespace std;

#define ll    long long int
#define ull   unsigned ll
#define pb    push_back
#define chota(a)  transform(a.begin(),a.end(),a.begin(),::tolower)
#define speed ios_base::sync_with_stdio(0)
#define newline cout<<"\n"

#define chec(x) (flag[x>>6]&(1<<((x>>1)&31)))
#define setc(x) (flag[x>>6]!=(1<<((x>>1)&31)))

string numbers = "0123456789";
string lower_case = "abcdefghijklmnopqrstuvwxyz";
string upper_case = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
string special_characters = "!@#$%^&*()-+";

bool no(char c){
  for(int i=0;i<numbers.size();i++)if(c==numbers[i])return true;

    return false;
}
bool low(char c){
  for(int i=0;i<lower_case.size();i++)if(lower_case[i]==c)return true;

    return false;
}
bool upper(char c){
  for(int i=0;i<upper_case.size();i++)if(upper_case[i]==c)return true;

    return false;
}
bool special(char c){
  for(int i=0;i<special_characters.size();i++)if(special_characters[i]==c)return true;
  
  return false;
}

int n;
string str;
int value;
int total;
bool x,y,z,w;
int main(){
  speed;
  cin>>n;
  cin>>str;
  for(int i=0;i<str.size();i++){
    if(no(str[i]))x++;
    else if(low(str[i]))y++;
        else if(upper(str[i]))z++;
            else if(special(str[i]))w++;
  }
  if(x==0)value++;
  if(y==0)value++;
  if(z==0)value++;
  if(w==0)value++;
  total=value+n;
  if(total<6)value+=(6-total);
  cout<<value<<endl;
}