#include<iostream>
#define REP(i,n) for( int i = 1; i <= n; i++ )
using namespace std;
int main(){
  int cnt = 0;
  int day[] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};

  REP(i,12){
    REP(j,day[i]){
      if( (j / 10) + (j % 10) == i ) cnt++;
    }
  }
  cout << cnt << endl;
}