<?php

/**
 * No.188 HAPPY DAY
 * 
 * @see https://yukicoder.me/problems/492
 */

const TARGET_YEAR = 2015;

$countHappyDay = 0;
$targetDate = new DateTime(TARGET_YEAR . "-01-01");
while ($targetDate->format("Y") == TARGET_YEAR) {
    $month = (int)$targetDate->format("m");
    list($tensPlace, $onesPlace) = str_split($targetDate->format("d"));
    if ($month == $tensPlace + $onesPlace) {
        $countHappyDay++;
    }
    $targetDate->add(new DateInterval("P1D"));
}

echo $countHappyDay . "\n";