#include <iostream>
using namespace std;

int main(){
    int month=12,day=31;
    int ans=0;
    for(int i = 1; i <= month; i++){
        for(int j = 1; j <= 31; j++){
            if(i == 2)if(j == 29) break;
            if(i == 4 || i == 6 || i == 9 || i == 11)if(j == 31) break;
            if(j / 10 == 0 &&  j == i){ ans++; continue; }
            if(j / 10 + j % 10 == i) ans++;
        }
    }
    cout << ans << endl;
    return 0;
}