/* -*- coding: utf-8 -*-
 *
 * 188.cc: No.188 HAPPY DAY - yukicoder
 */

#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<iostream>
#include<string>
#include<vector>
#include<map>
#include<set>
#include<stack>
#include<list>
#include<queue>
#include<deque>
#include<algorithm>
#include<numeric>
#include<utility>
#include<complex>
#include<functional>
 
using namespace std;

/* constant */

int doms[] = {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};

/* typedef */

/* global variables */

/* subroutines */

/* main */

int main() {
  int cnt = 0;

  for (int x = 1; x <= 12; x++) {
    for (int y = 1; y <= doms[x]; y++) {
      int sum = y / 10 + y % 10;
      if (x == sum) cnt++;
    }
  }

  printf("%d\n", cnt);
  return 0;
}