c = 0
L = [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]
for m in range(1, 13):
    for d in range(1, L[m -1] + 1):
        if m == d // 10 + d % 10:
            c += 1
print(c)