#include<iostream>
using namespace std;
int main(void)
{
	int month[13] = { 0,31,28,31,30,31,30,31,31,30,31,30,31 };
	int i, j, ans = 0;
	
	for (i = 1; i < 13; i++) {
		for (j = 1; j <= month[i]; j++) {
			if (i == j % 10 + j / 10)ans += 1;
		}
	}

	cout << ans << endl;

	return 0;
}