#!/bin/ruby

def minimumNumber(n, password)
  m = 0
  m+=1 unless /[0-9]/ =~ password
  m+=1 unless /[a-z]/ =~ password
  m+=1 unless /[A-Z]/ =~ password
  m+=1 unless /[@!\#$%^&*()\-+]/ =~ password
  
  return [m,6-n].max
end


n = gets.strip.to_i
password = gets.strip
answer = minimumNumber(n, password)
puts answer