M = [0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]
ans = 0
for i in range(1, 13):
    for j in range(1, M[i]+1):
#        Y = j%10 + j//10
#        X = i
        if i == (j%10 + j//10):
            ans += 1
print(ans)