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

n = input()
s = raw_input()
cnt = 4

for i in s:
	if i in numbers:
		cnt=cnt-1;
		break

for i in s:
	if i in lower_case:
		cnt=cnt-1;
		break

for i in s:
	if i in upper_case:
		cnt=cnt-1;
		break

for i in s:
	if i in special_characters:
		cnt=cnt-1;
		break

if n+cnt<6:
	cnt+=(6-n-cnt );

print cnt