#include <iostream>
#include <algorithm>
#include <vector>
#include <string>
#include <iomanip>
#include <cmath>
#include <functional>
using namespace std;
#define diff(x,y) ((x > y) ? (x - y) : (y - x))
#define us(x) (x > 0) ? x : x * -1
#define lli long long int

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