#include<bits/stdc++.h>
#define rep(i,a,n) for (int i = a;i < n;i++)
#define per(i,n,a) for (int i = n-1;i >= a;i--)
using namespace std;

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