#include<iostream>

using namespace std;

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