#include <iostream>
#include <numeric>
#include <algorithm>
#include <string>
#include <vector>
#include <cmath>
#include <queue>

#define rep(i, a) FOR(i, 0, a)
#define FOR(i, a, b) for(int i = a; i < b; ++i)

int day[12] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };

int main(){
	int cnt = 0;
	rep(i, 12)rep(j, day[i]){
		int sum = j % 10 + j / 10 % 10;
		if (sum == i)++cnt;
	}
	std::cout << cnt << std::endl;
	return 0;
}