import java.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;

public class Solution {

    static int minimumNumber(int n, String password) {
        String pattern = "(?=.*[0-9])(?=.*[a-z])(?=.*[A-Z])(?=.*[@#$%^&+=])(?=\\S+$).{8,}";
	      int ans=0;
	      if(password.matches(pattern))
	        {
	            return ans;
	        }
	      else
	      {
	    	  int count=0,count1=0,count2=0,count3=0;
	    	  for(int i=0;i<password.length();i++)
	    	  {
	    		  if((int)password.charAt(i)>=97 && (int)password.charAt(i)<=122)
	              {
	                  count++;
	              }
	              if((int)password.charAt(i)>=65 && (int)password.charAt(i)<=90)
	              {
	                  count1++;
	              }
	               if((int)password.charAt(i)>=48 && (int)password.charAt(i)<=57)
	              {
	                  count2++;
	              }
	               
	               if(q(password.charAt(i)))
	               {
	            	   count3++;
	               }
	               
	    	  }
	    	  
	    	  if(count==0)
	    	  {
	    		  ans++;
	    	  }
	    	  if(count1==0)
	    	  {
	    		  ans++;
	    	  }
	    	  if(count2==0)
	    	  {
	    		  ans++;
	    	  }
	    	  if(count3==0)
	    	  {
	    		  ans++;
	    	  }
	    	  
	    	  if(ans+password.length()<6)
	    	  {
	    		  ans=6-password.length();
	    	  }
	    	 
	    	  
	    	  
	    	 return ans;
	    	  
	      }
	   }



    

static boolean q(char a)
{
	boolean d=false;
	String c="!@#$%^&*()-+";
	
	for(int h=0;h<c.length();h++)
	{
		if(a==c.charAt(h))
		{
			d=true;
		}
	}
	
	
	
	
	return d;
}

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int n = in.nextInt();
        String password = in.next();
        int answer = minimumNumber(n, password);
        System.out.println(answer);
        in.close();
    }
}