#!/bin/python

import sys

def minimumNumber(n, password):
    # Return the minimum number of characters to make the password strong
    num = list("0123456789")
    low = list("abcdefghijklmnopqrstuvwxyz")
    upp = list("ABCDEFGHIJKLMNOPQRSTUVWXYZ")
    spe = list("!@#$%^&*()-+")
    ans=0
    f=1
    for i in password:
        if i in num:
            f=0
            break
    if f:
        ans+=1
    f=1
    for i in password:
        if i in low:
            f=0
            break
    if f:
        ans+=1
    f=1
    for i in password:
        if i in upp:
            f=0
            break
    if f:
        ans+=1
    f=1
    for i in password:
        if i in spe:
            f=0
            break
    if f:
        ans+=1
    f=1
    if (len(password)+ans)<6:
        ans+=6-(len(password)+ans)
    return ans
if __name__ == "__main__":
    n = int(raw_input().strip())
    password = raw_input().strip()
    answer = minimumNumber(n, password)
    print answer