#include <iostream>
using namespace std;

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