Online PHP editor | refs for 42X7s

<?php $symbolstocheck = [1, 1, 3, 1, 5]; $prev = null; $keyz = -1; $res = []; foreach ($symbolstocheck as $value) { $value = (int)$value; if ($value !== $prev) { $keyz++; } $prev = $value; if (!isset($res[$keyz])) { $res[$keyz] = ''; } $res[$keyz] .= $value; } var_dump($res);