using System;
using System.Collections.Generic;
using System.Linq;

namespace No188
{
	class MainClass
	{
		public static void Main (string[] args)
		{
			var pairs = new[]{
				new Tuple<int,int>(1,31),
				new Tuple<int,int>(2,28),
				new Tuple<int,int>(3,31),
				new Tuple<int,int>(4,30),
				new Tuple<int,int>(5,31),
				new Tuple<int,int>(6,30),
				new Tuple<int,int>(7,31),
				new Tuple<int,int>(8,31),
				new Tuple<int,int>(9,30),
				new Tuple<int,int>(10,31),
				new Tuple<int,int>(11,30),
				new Tuple<int,int>(12,31)
			};

			int total = 0;
			foreach (var keyValue in pairs) {
				var month = keyValue.Item1;
				for (int day = 1; day <= keyValue.Item2; day++) {
					int t = day % 10;
					int d = day / 10;
					int s = t + d;
					if (month == s) {
						total++;
					}
				}
			}
			Console.WriteLine (total.ToString ());
		}
	}
}