รบกวนช่วยคิดอัลกอรึทึ่มในการแสดงผลจาก array หน่อยครับ

<?php
$a = array('1','2','3','4','5','6');

$count_arr = count($a)-1;
$total_loop = 0;
$num_loop = 0;

for($c=0;$c<=count($a);$c++){
	for($i=0;$i<=$num_loop;$i++){
		while ($total_loop <= $count_arr) {
			$b = $total_loop;
			if($total_loop >= $count_arr)
			{
				if($i>0){
					$total_loop +=$i;
				}
			}
			echo $a[$total_loop]." ";
			$total_loop = $b;
			$total_loop++;
		}
		echo "<br>";
		$total_loop = 0;
	}
	echo "<br>";
	$num_loop++;
	$count_arr--;
	$total_loop = 0;
}
?>