import java.util.Scanner;

public class Main {
    public static void main(String []args){
        int[] lastDay = {0,31,28,31,30,31,30,31,31,30,31,30,31,30};
        int ansCount = 0;
        for(int month = 1; month <= 12; month++){
            for(int day = 1; day <= lastDay[month]; day++){
                if(month == day / 10 + day % 10){
                    ansCount++;
                }
            }
        }
        System.out.println(ansCount);
    }
}