#include <iostream>
#include <fstream>
#include <vector>
#include <string>
#include <algorithm>
using namespace std;

int main(){

  vector<int> day = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
  int ans = 0;
  for (int i = 0; i < 12; i++) {
    for (int j = 0; j < day[i]; j++) {
      int c = ((j + 1) / 10) + ((j + 1) % 10);
      if (c == i + 1) {
        ans++;
      }
    }
  }
  cout << ans << "\n";
	return 0;
}