#include<stdio.h>
#include <vector>
#include <list>
#include <map>
#include <set>
#include <queue>
#include <stack>
#include <algorithm>
#include <sstream>
#include <iostream>
#include <string>
#include <stdio.h>

using namespace std;

int main() {

	int month[13] = { -1, 31, 29, 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]; j++) {
			if (i == j/10 + j%10) {
				cnt++;
			}
		}
	}

	cout << cnt << endl;

	return 0;
}