def ccnt(m, i):
    c = 0
    for d in range(10, i + 1):
        a, b = map(int, str(d))
        if a + b == m:
            c += 1
            #print m,a,b
    return c

cnt = 0
for m in range(1, 13):
    if m < 10:
        #print m, 0, m
        cnt += 1
    if m == 2:
        cnt += ccnt(2, 28)
    elif m in (4, 6, 9, 11):
        cnt += ccnt(m, 30)
    else:
        cnt += ccnt(m, 31)

print cnt