#!/bin/python3

import sys


def minimumNumber(n, password):
    res = list(password)
    inc = 0
    special = '!@#$%^&*()-+'
    smal = 'abcdefghijklmnopqrstuvwxyz'
    uper = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'
    num = '0123456789'
    chk = False
    for i in special:
        if i in res:
            chk = True
            break

    if not chk:
        inc = inc + 1

    chk = False
    for i in smal:
        if i in res:
            chk = True
            break

    if not chk:
        inc = inc + 1

    chk = False
    for i in uper:
        if i in res:
            chk = True
            break

    if not chk:
        inc = inc + 1

    chk = False
    for i in num:
        if i in res:
            chk = True
            break

    if not chk:
        inc = inc + 1

    if inc + n >= 6:
        return inc
    else:
        p = 6 - (n + inc)
        return (p + inc)


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