<?php
$i = true;
$array = array('red');
foreach($array as $key => & $value) {
    echo $value . '<br />';
    if ($i === true) {
          $a1= $array;
          $a2= array($value);
          $result=array_diff($a1,$a2);
          print_r($result);
 
         $others = array('white', 'yellow');
         if(!empty($result)){
         	$array =  array_merge($others,$result);
         } else {
         		$array =  array_merge($others,$array);
         }
    }
    $i = false;
}

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