foreach

<?php
$arr = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
$c = 0;
foreach ($arr as &$v) {
  echo <<<EOS
<div class="content01">
<p>hogehoge{$v}</p>
</div>

EOS;
  $c++;
  if ($c % 5 == 0) echo '<div id="content_area">', PHP_EOL;
}