#include <iostream>
using namespace std;

int main(void){
  int mday[] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};

  int cnt = 0;
  for(int i=0;i<12;i++){
    for(int j=0;j<mday[i];j++){
      int a = j % 10;
      int b = (j/10) % 10;
      if(i == (a+b)) cnt++;
    }
  }
  cout << cnt << endl;
}