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

public class Solution {

    
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int n = in.nextInt();
        String pass = in.next();
        int d=0;
        int u=0;
        int l=0;
        int i,j;
        int s=0;
        for(i=0;i<n;i++)
        {
            if(pass.charAt(i)=='1'||pass.charAt(i)=='0'||pass.charAt(i)=='2'||pass.charAt(i)=='3'||pass.charAt(i)=='4'||pass.charAt(i)=='5'||pass.charAt(i)=='6'||pass.charAt(i)=='7'||pass.charAt(i)=='8'||pass.charAt(i)=='9')
            {
                d=1;
            }
            else if(pass.charAt(i)=='!'||pass.charAt(i)=='@'||pass.charAt(i)=='#'||pass.charAt(i)=='$'||pass.charAt(i)=='%'||pass.charAt(i)=='^'||pass.charAt(i)=='&'||pass.charAt(i)=='*'||pass.charAt(i)=='('||pass.charAt(i)==')'||pass.charAt(i)=='-'||pass.charAt(i)=='+')
            {
                s=1;
            }
                
            else if(Character.isUpperCase(pass.charAt(i)))
            {
                u=1;
            }
            else if(Character.isLowerCase(pass.charAt(i)))
            {
                l=1;
            }
            
        }
        int ans=0;
        if(d==0)
        {
            ans++;
        }
        if(s==0)
        {
            ans++;
        }
        if(u==0)
        {
            ans++;
        }
        if(l==0)
        {
            ans++;
        }
        if((ans+n)>=6)
        {
            System.out.println(ans);
        }
        else
        {
            ans=ans+(6-(ans+n));
            System.out.println(ans);
        }
    }
}