import java.io.*;
import java.util.*;

public class A{
	InputStream is;
	PrintWriter out;
	String INPUT = "";
	
	
	
	char str[];
	int n;
	public void solve(){
		n=ni();
		str=ns().toCharArray();
		int ans=4;
		for(int i=0;i<str.length;i++){
			if(str[i]<='z' && str[i]>='a'){
				ans-=1;break;
			}
		}
		for(int i=0;i<str.length;i++){
			if(str[i]<='Z' && str[i]>='A'){
				ans-=1;break;
			}
		}
		for(int i=0;i<str.length;i++){
			if(str[i]<='9' && str[i]>='0'){
				ans-=1;break;
			}
		}
		for(int i=0;i<str.length;i++){
			if(str[i]=='!' || str[i]=='#' || str[i]=='@' || str[i]=='$' || str[i]=='%' || str[i]=='^' || str[i]=='&' || str[i]=='*' || str[i]=='(' || str[i]==')' || str[i]=='-' || str[i]=='+' ){
				ans-=1;break;
			}
		}
		if(n>=6)out.println(ans);
		else if(n+ans>=6)out.println(ans);
		else out.println(6-n);
	}
	

	void run(){
		is = new DataInputStream(System.in);
		out = new PrintWriter(System.out);
		int t=1;while(t-->0)solve();
		out.flush();
	}
	public static void main(String[] args)throws Exception{new A().run();}
	//Fast I/O code is copied from uwi code.
	private byte[] inbuf = new byte[1024];
	public int lenbuf = 0, ptrbuf = 0;
	private int readByte(){
		if(lenbuf == -1)throw new InputMismatchException();
		if(ptrbuf >= lenbuf){
			ptrbuf = 0;
			try { lenbuf = is.read(inbuf); } catch (IOException e) { throw new InputMismatchException(); }
			if(lenbuf <= 0)return -1;
		}
		return inbuf[ptrbuf++];
	}
	private boolean isSpaceChar(int c) { return !(c >= 33 && c <= 126); }
	private int skip() { int b; while((b = readByte()) != -1 && isSpaceChar(b)); return b; }
	private double nd() { return Double.parseDouble(ns()); }
	private char nc() { return (char)skip(); }
	private String ns(){
		int b = skip();
		StringBuilder sb = new StringBuilder();
		while(!(isSpaceChar(b))){ // when nextLine, (isSpaceChar(b) && b != ' ')
			sb.appendCodePoint(b);
			b = readByte();
		}
		return sb.toString();
	}
	private char[] ns(int n){
		char[] buf = new char[n];
		int b = skip(), p = 0;
		while(p < n && !(isSpaceChar(b))){
			buf[p++] = (char)b;
			b = readByte();
		}
		return n == p ? buf : Arrays.copyOf(buf, p);
	}
	private char[][] nm(int n, int m){
		char[][] map = new char[n][];
		for(int i = 0;i < n;i++)map[i] = ns(m);
		return map;
	}
	private int[] na(int n){
		int[] a = new int[n];
		for(int i = 0;i < n;i++)a[i] = ni();
		return a;
	}
	private int ni(){
		int num = 0, b;
		boolean minus = false;
		while((b = readByte()) != -1 && !((b >= '0' && b <= '9') || b == '-'));
		if(b == '-'){
			minus = true;
			b = readByte();
		}
		
		while(true){
			if(b >= '0' && b <= '9'){
				num = num * 10 + (b - '0');
			}else{
				return minus ? -num : num;
			}
			b = readByte();
		}
	}
	private long nl(){
		long num = 0;
		int b;
		boolean minus = false;
		while((b = readByte()) != -1 && !((b >= '0' && b <= '9') || b == '-'));
		if(b == '-'){
			minus = true;
			b = readByte();
		}
		
		while(true){
			if(b >= '0' && b <= '9'){
				num = num * 10 + (b - '0');
			}else{
				return minus ? -num : num;
			}
			b = readByte();
		}
	}
	
}