month_list = [i for i in range(1, 13)]
day_list = [str(i) for i in range(1, 32)]
count = 0
for i in month_list:
    n = 0
    for j in day_list:
        for k in range(len(j)):
            n += int(j[k])
        if i == n:
            count += 1
print(count)