count = 0
for month in range(1,12+1):
    for day in range(1,32):
        if (month == 2 and day >= 29) or ((month == 4 or month == 6 or month == 9 or month == 11) and day >= 31):
            continue
        day_10 = day // 10
        day_1 = day - ((day // 10) * 10)
        if month == day_10 + day_1:
            count += 1
print(count)