month = [31,28,31,30,31,30,31,31,30,31,30,31]
cnt = 0
for i in range(12):
    d = month[i]
    for j in range(1, d +1):
        d1, d2 = divmod(j, 10)
        if i +1 == d1 + d2:
            cnt += 1

print(cnt)