#include <iostream>
using namespace std;
int main(){
	int days[12]={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<days[i];j++){
			if(i+1 == (j/10)+(j%10))cnt++;
		}
	}
	cout << cnt << endl;
}