#include <bits/stdc++.h>

using namespace std;

int n,i,a,b,c,d,t;
string s;

int main() {
    int n;
    cin >> n;
    cin >> s;
    for(i=0;i<s.size();i++){
      if(s[i]>='0' && s[i]<='9')
        a++;
      if(s[i]>='a' && s[i]<='z')
        b++;
      if(s[i]>='A' && s[i]<='Z')
        c++;
      if(s[i]=='!' || s[i]=='@' || s[i]=='#' || s[i]=='$' || s[i]=='%' || s[i]=='^' || s[i]=='&' || s[i]=='*' || s[i]=='(' || s[i]==')' || s[i]=='-' || s[i]=='+')
        d++;
    }
  //!@#$%^&*()-+
    if(a==0)
      t++;
    if(b==0)
      t++;
    if(c==0)
      t++;
    if(d==0)
      t++;
    if(t+s.size()<6)
      cout<<6-s.size()<<endl;
  else
    cout << t << endl;
  ////for(i=int('!');i<=int('+');i++)
  //  cout<<char(i)<<' ';
 /// cout<<endl;
    return 0;
}