#include<iostream>
int main() {
	int daymax[12] = { 31,28,31,30,31,30,31,31,30,31,30,31 };
	int count = 0;
	for (int i = 0; i<12; i++) {
		for (int j = 0; j < daymax[i]; j++) {
            int a = daymax[i]%10;
            int b = daymax[i]/10;
            if(i == a+b){
                count ++;
            }
		}
	}
	std::cout<<count<<std::endl;
	return 0;
}