#include <iostream>
#include <stdio.h>
#include <cmath>
#include <algorithm>
#include <vector>

#define FOR(i, a, b) for (int i = a; i < b; i++)
#define FORN(i, a, b) for (int i = a; i <= b; i++)
#define P(s) cout << s << endl
#define PC(condition, _true, _false) if (condition) _true; else _false;
#define toInt(_char) _char - '0'

using namespace std;
//
// Created by karayuu on 2019-03-03.
//

int main() {
    int c[12] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};

    int count = 0;

    FORN(i, 1, 12) {
        FORN(j, 1, c[i]) {
            if (j / 10 + j % 10 == i) {
                count++;
            }
        }
    }

    P(count);
}