happy_day = 0
for i in range(12):
    if i == 0 or i == 2 or i == 4 or i == 6 or i == 7 or i == 9 or i ==11:
        for j in range(31):
            if i+1 == (j+1) // 10 + (j+1) % 10:
                happy_day += 1
    elif i == 1:
        for j in range(28):
            if i+1 == (j+1) // 10 + (j+1) % 10:
                happy_day += 1
    else:
        for j in range(30):
            if i+1 == (j+1) // 10 + (j+1) % 10:
                happy_day += 1
print(happy_day)