Alternating Array Between Left And Right

[-Karl-]

Hello,

 

I need a more efficient way of alternating an array in order to display them left and right.

 

At the moment I have my HTML:

<div class="left">
 //This floats everything within the div to the left
 //Echo buildLeft
</div>
<div class="right">
 //This floats everything within the div to the right
 //Echo buildRight
</div>

 

Then I have the following PHP code in order to take the current array, which is all the results and manipulate it:

 function buildLeft($array) {
	 $new_array = array();
	 $i = 0;
	 $count = count($array);
	 while($i < $count) {
		 $new_array[] = $array[$i];
		 $i = $i+2;
	 }
	 return $new_array;
 }

 function buildRight($array) {
	 $new_array = array();
	 $i = 1;
	 $count = count($array);
	 while($i < $count) {
		 $new_array[] = $array[$i];
		 $i = $i+2;
	 }
	 return $new_array;
 }

 

The code works fine and does what I need it to do, but I just don't think it's very efficient, especially when the beginning array could be quite large, then I'm running it through both of these functions.

 

Any ideas?

Edited November 1, 2012 by -Karl-

[ManiacDan]

You could run through the array once:

$left = array();
$right = array();
$l = true;
foreach ( $arr as $val ) {
  if ( $l ) {
    $left[] = $val;
  } else {
    $right[] = $val;
  }
  $l = !$l;
}

[-Karl-]

You could run through the array once:

$left = array();
$right = array();
$l = true;
foreach ( $arr as $val ) {
if ( $l ) {
$left[] = $val;
} else {
$right[] = $val;
}
$l = !$l;
}

Hmm, but how would I return it from the function?

Edited November 1, 2012 by -Karl-

[-Karl-]

Nevermind, fixed it myself:

 

    function buildPosts($array) {
	    $new_array = array('left' => array(), 'right' => array());
	    $i = 0;
	    foreach($array as $val) {
		    if($i == 0) {
			    $new_array['left'][] = $val;
			    $i = 1;
		    } else {
			    $new_array['right'][] = $val;
			    $i = 0;
		    }
	    }
	    return $new_array;
    }

 

Thanks for the advice though guys!