counter = 0
for month in range(1, 13):
    if month == (1 or 3 or 5 or 7 or 8 or 9 or 10 or 12):
        for day in range(1, 32):
            if month == (day // 10) + (day % 10):
                counter += 1
    elif month == (4 or 6 or 9 or 11):
        for day in range(1, 31):
            if month == (day // 10) + (day % 10):
                counter += 1
    else:
        for day in range(1, 29):
            if month == (day // 10) + (day % 10):
                counter += 1

print(counter)