#include <bits/stdc++.h>
using ll = long long;
using llu = long long unsigned;

using namespace std;

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