content: import java.io.*;
  import java.math.*;
  import java.security.*;
  import java.text.*;
  import java.util.*;
  import java.util.concurrent.*;
  import java.util.regex.*;
  
  public class Solution {
  
  	// Complete the minimumNumber function below.
  	static int minimumNumber(int n, String password) {
  		int digit = 0;
  		int lowerCase = 0;
  		int upperCase = 0;
  		int special = 0;
  		for (int i = 0; i < password.length(); i++) {
  			char c = password.charAt(i);
  			if (isDigit(c)) { digit++; }
  			if (isLowerCase(c)) { lowerCase++; }
  			if (isUpperCase(c)) { upperCase++; }
  			if (isSpecial(c)) { special++; }
  		}
  		int miss = 0;
  		if (digit == 0) { miss++; }
  		if (lowerCase == 0) { miss++; }
  		if (upperCase == 0) { miss++; }
  		if (special == 0) { miss++; }
  		int missingLength = (password.length() - 6 < 0) ? 6 - password.length(): 0;
  		if (miss < missingLength) {
  			return missingLength;
  		}
  		return miss;
  	}
  
  	static boolean isDigit(char c) { return 48 <= c && c <= 57; }
  	static boolean isLowerCase(char c) { return 97 <= c && c <= 122; }
  	static boolean isUpperCase(char c) { return 65 <= c && c <= 90; }
  	static boolean isSpecial(char c) {
  		return (
  				c == '!' || c == '@' || c == '#' || c == '$' || c == '%' || c == '^' ||
  						c == '&' || c == '*' || c == '(' || c == ')' || c == '-' || c == '+'
  		);
  	}
  
  	private static final Scanner scanner = new Scanner(System.in);
  
  	public static void main(String[] args) throws IOException {
  		BufferedWriter bufferedWriter = new BufferedWriter(new FileWriter(System.getenv("OUTPUT_PATH")));
  
  		int n = scanner.nextInt();
  		scanner.skip("(\r\n|[\n\r\u2028\u2029\u0085])?");
  
  		String password = scanner.nextLine();
  
  		int answer = minimumNumber(n, password);
  
  		bufferedWriter.write(String.valueOf(answer));
  		bufferedWriter.newLine();
  
  		bufferedWriter.close();
  
  		scanner.close();
  	}
  }
  