<?php
// $a = date('md',strtotime('20150132'.'+1 day'));
// $a = intval($a);
$year = 2015;
$month_num = 12;
$happyday = 0;
for($i=1;  $i <= $month_num; $i++){
    $ii = sprintf('%02d', $i);
    for($x=1; ; $x++){
        $m = intval(date('m', strtotime($year . $ii . '01 +' . ($x-1) . ' day')));
        if($m !== $i){
            break;
        }
        $d = date('d', strtotime($year . $ii . '01 +' . ($x-1) . ' day'));
        if($d > 9){
            $p_d = substr($d, 0, 1);
            $a_d = substr($d, 1, 1);
        } else{
            $p_d = 0;
            $a_d = intval(substr($d, 1, 1));
        }
        $d_sum = $p_d + $a_d;
        // echo '$d : ' . $d . "  ";
        // echo '$d_sum : ' . $d_sum . "\n";
        if($d_sum === $m){
            $happyday += 1;
        }
    }
}
echo $happyday;