#include <iostream>
using namespace std;

int main() {
    int ans = 0, day[] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
    for (int i = 0; i < 12; i++) {
        for (int j = 1; j <= day[i]; j++) {
            if (i+1 == j%10+j/10) ans++;
        }
    }
    cout << ans << endl;
}