import static java.lang.Character.isLetter;
import static java.lang.Character.isLowerCase;
import static java.lang.Character.isUpperCase;
import java.util.*;
public class Solution {
    public static void main(String[]args)
    {
        Scanner sc=new Scanner(System.in);
      int n=sc.nextInt();
      String s=sc.next();
      int i;int ans=0;
      int u=0;
      int l=0;
      int num=0,sp=0;
       for(i=0;i<n;i++)
          {
              if(Character.isDigit(s.charAt(i)))
                  num+=1;
              char c=s.charAt(i);
              if(c=='!'||c=='@'||c=='#'||c=='^'||c=='*'||c=='('||c==')'||c=='&'||c=='$'||c=='%'||c=='-'||c=='+')
                  sp+=1;
              if(isUpperCase(c))
                  u+=1;
              if(isLowerCase(c))
                  l+=1;
          }
      if(n<6)
      {
          ans=6-n;
          int f=ans;
         if(l==0)
             f-=1;
         if(u==0)
             f-=1;
         if(num==0)
             f-=1;
         if(sp==0)
             f-=1;
         if(f>=0)
             System.out.println(ans);
         else
             System.out.println(ans-f);
      }
      else
      {
          int f=0;
         if(l==0)
             f-=1;
         if(u==0)
             f-=1;
         if(num==0)
             f-=1;
         if(sp==0)
             f-=1;
         System.out.println(-f);
      }
    }
}