#include <iostream>
using namespace std;

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

	for(int m=1; m<=12; m++){
		for(int d=1; d<=g[m-1]; d++){
			if(m == (d/10)+(d%10))
				s++;
		}
	}

	cout << s;
}