#!/bin/python

import sys

def minimumNumber(n, password):
    digit=0
    lowerc=0
    upperc=0
    special=0
    for c in password:
        if c.isdigit(): digit+=1
        elif c.isalpha():
            if c.isupper(): upperc+=1
            else: lowerc+=1
        elif c in ['!','@','#','$','%','^','&','*','(',')','-','+']: special+=1
    ans=0
    if digit<1: ans+=1
    if lowerc<1: ans+=1
    if upperc<1: ans+=1
    if special<1: ans+=1
    if n+ans<6: return (6-n-ans)+ans
    return ans
            
        

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