#include <bits/stdc++.h>
using namespace std;

int m = 0;
int a[12] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };

int main()
{
	for (int i = 1; i <= 12; i++) {
		for (int j = 1; j <= a[i - 1]; j++) {
			if (j % 10 + j / 10 == i) {
				m++;
			}
		}
	}

	cout << m << endl;
}