#include <iostream>
using namespace std;
int main(){
    const int days[12]={
        31,28,31,30,31,30,
        31,31,30,31,30,31
    };
    int cnt=0;
    for(int Y=1;Y<=12;Y++){
        for(int X=1;X<=days[Y-1];X++){
            if(X/10+X%10==Y)cnt++;
        }
    }
    cout << cnt << endl;
    return 0;
}