#include<iostream>
#include<cmath>
using namespace std;

int main(){
   int days[12] = {31,28,31,30,31,30,31,31,30,31,30,31};
   int HAPPY_DAY = 0;

   for(int i = 0; i < 12; i++){
      for(int j = 0; j < days[i]; j++){
         int y1=(j+1)%10, y2=(j+1)/10;
         if(i+1 == y1+y2){
            HAPPY_DAY++;
         }
      }
   }

   cout << HAPPY_DAY << endl;
   return 0;
}