class Problem0188:
    def solve(this):
        days = [31,28,31,30,31,30,31,31,30,31,30,31]

        res = 0
        for i in range(1, 13):
            for j in range(1, days[i-1]):
                if i == (j // 10) + (j % 10):
                    res += 1

        print(res)

if __name__ == "__main__":
    problem = Problem0188()
    problem.solve()