#include <iostream>
#include <algorithm>
#include <vector>
#include <string>
#include <cmath>
#include <iomanip>
#include <map>
using namespace std;
typedef long long LL;

int main(){
    int day[] = {31,28,31,30,31,30,31,31,30,31,30,31};
    int cnt = 0;
    for(int m = 1; m <= 12; m++){
        for(int d = 1; d <= day[m-1]; d++){
            if(d%10+d/10 == m) cnt++;
        }
    }
    cout << cnt << endl;
    return 0;
}