#include <stdio.h>

int main()
{
	int count = 0;
	int a[12] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
	for (int i = 0; i < 12; i++)
		for (int j = 1; j <= a[i]; j++)
			if (i + 1 == (j / 10 + j % 10))
				count++;
	printf("%d\n", count);
	return 0;
}