Stagger column number by row

staggerCol.php

<?php
$items = array_fill(0, 16, 'item');
$col = 0;
$row = 0;
foreach($items as $item) {
  $col++;
  if ($col > 4) {
    $col = 1;
    $row++;
  }
  $num = $col + $row > 4 ? $col + $row - 4 : $col + $row;

  echo $num;
}
?>