Y = range(1,32)
lst_Y = list(Y)
X = range(1,13)
lst_X = list(X)
result = -1

for i in lst_Y:
    y = lst_Y[i - 1]
    for n in lst_X:
        if n == y // 10 + y % 10:
            result = result + 1

print(result)