#include <iostream>

using namespace std;

bool judge(int m, int d)
{
	return m == d / 10 + d % 10 ? true : false;
}

int main()
{
	int ans = 0;
	for (int i = 1; i <= 12; i++)
	{
		for (int j = 1; j <= 31; j++)
		{
			if (i == 2 && j > 28)
			{
				break;
			}
			if (j > 30 && (i == 4 || i == 6 || i == 9 || i == 11))
			{
				break;
			}
			ans += judge(i, j);
		}
	}
	cout << ans << endl;
}