#include <iostream>
#include <string>

using namespace std;
typedef long long int lint;

int main()
{
	lint count = 0, d[] = { 0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
	for (lint m = 1; m <= 12; m++)
		for(lint i = 1; i <= d[m]; i++)
			if (m == i % 10 + i / 10)
				count++;
	cout << count << endl;
	return 0;
}