#include <iostream>
#include <vector>
using namespace std;

int main(){
    vector<int> days = {31,28,31,30,31,30,31,31,30,31,30,31};
    int cnt = 0;
    for (int m = 1; m <= 12; m++){
        for (int d = 1; d <= days[m-1]; d++){
            if (m == d % 10 + d / 10)
                cnt++;
        }
    }
    cout << cnt << endl;
    return 0;
}