function Main() {
	let month;
  let count = 0;
  let big_monthes = [1, 3, 5, 7, 8, 10, 12];

  // 月ごとにhappydayの有無を判定
  function judge_happyday(max_day) {
  	for (var j = 1; j <= max_day; j++) {
  		let day = j;
			day = ("00" + day).slice(-2);
  		day = day.split('');
  		let day_10 = day[0];
  		let day_1 = day[1];
  		sum = parseInt(day_10) + parseInt(day_1);
  		if (sum == month) {
  			count++;
  		}
  	}
  }

  for (var i = 1; i <= 12; i++) {
  	month = i;
  	if (month == 2) {
  		judge_happyday(28);
  	} else if (big_monthes.indexOf(month) != -1) {
	  	judge_happyday(31);
  	} else {
  		judge_happyday(30);
  	}
  }
  console.log(count);
}
Main(require('fs').readFileSync('/dev/stdin', 'utf8'));