#include <iostream>

using namespace std;

int main() {
	static const int days[] = { 0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
	int happyDays = 0;
	for (int month = 1; month <= 12; ++month) {
		for (int day = 1; day <= days[month]; ++day) {
			if (month == (day / 10) + (day % 10)) {
				++happyDays;
			}
		}
	}
	cout << happyDays << endl;
	return 0;
}