numbers = "0123456789"
lower_case = "abcdefghijklmnopqrstuvwxyz"
upper_case = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
special_characters = "!@#$%^&*()-+"

num = False
low_case = False
upp_case = False
spec = False

n = int(raw_input())
s = raw_input()
res = 0
for char in s:
    if not num and char in numbers:
        num = True
    elif not spec and char in special_characters:
        spec = True
    elif not low_case and char in lower_case:
        low_case = True
    elif not upp_case and char in upper_case:
        upp_case = True

        
#print num, low_case, upp_case, spec
if not num: res += 1
if not low_case: res += 1
if not upp_case: res += 1
if not spec: res += 1

if n + res < 6:
    res += (6-(res+n))
print res