#!/bin/python3

import sys

def minimumNumber(n, password):
    tcount=0
    ucount=0
    lcount=0
    dcount=0
    scount=0
    special_chars = "!@#$%^&*()-+"
    for i in password:
        if i.isupper():
            ucount+=1
        if i.islower():
            lcount+=1
        if i.isdigit():
            dcount+=1
        if i in special_chars:
            scount+=1
    if ucount==0:
        tcount+=1
    if lcount==0:
        tcount+=1
    if dcount==0:
        tcount+=1
    if scount==0:
        tcount+=1
    if tcount+n < 6:
        tcount=6-n
    return(tcount)

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