import sys
import math

inputs = []
unique=[]
counter=0
line = sys.stdin.readline()
inputs.append(line.replace("\n",""))
while(line):
	line = sys.stdin.readline()
	if line=="\n":
		break
	inputs.append(line.replace("\n",""))

def getUni(s):
	st = ""
	for c in "123456789":
		if(s.find(c)!=-1):
			st += c
	return st

for i in inputs:
	it = getUni(i)
	if counter==0:
		counter=(int(i))
		counter+=1
	counter-=1
print(len(unique))