#!/bin/python3

import sys

def minimumNumber(n, password):
         # Return the minimum number of characters to make the password strong
    n1=0;
    l=0;
    u=0;
    s=0;
    c=0
    numbers = "0123456789"
    lower_case = "abcdefghijklmnopqrstuvwxyz" 
    upper_case = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
    special_characters = "!@#$%^&*()-+"
    for i in range(n):
        if(password[i] in numbers):
              n1+=1;
        if(password[i] in lower_case):
              l+=1;
        if(password[i] in upper_case):
              u+=1;
        if(password[i] in special_characters):
              s+=1;

    
    if(n1==0):
        c+=1
        n+=1
    if(u==0):
        c+=1
        n+=1
    if(l==0):
        c+=1
        n+=1
    if(s==0):
        c+=1
        n+=1
    if(n<6):
        c+=6-n;
        
    return c
        
        
   
          

if __name__ == "__main__":
    n = int(input().strip())
    password = input().strip()
    answer = minimumNumber(n, password)
    print(answer)