#include <iostream>

using namespace std;


int main()
{
	int ans = 0;
	int days[] = { 31,28,31,30,31,30,31,31,30,31,30,31 };

	for (int i = 0; i <= 12; i++)
	{
		
		for (int j = 0; j < days[i]; j++)
		{
			int digit1 = j / 10;
			int digit2 = j % 10;

			int total = digit1 + digit2;

			if (i + 1 == total)
			{
				ans++;
			}
		}
	}
	cout << ans << endl;
	return 0;
}