import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int [] Days = {31,28,31,30,31,30,31,31,30,31,30,31};
        int count=0;
        for(int i=1; i<=12; i++){
            for(int j=1; j<=Days[i-1]; j++){
                int a10 = j/10;
                int a01 = j%10;
                if(i==a10+a01){
                    count++;
                }
            }
        }
        System.out.println(count);
    }
}