#include <iostream>
using namespace std;
int main() {
    int count = 0;
    int days[12] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
    for(int m = 1; m <= 12; m++){
        for(int d = 1; d <= days[m-1]; d++){
            if(m == d/10 + d%10) count++;
        }
    }
    cout << count << endl;
    return 0;
}