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<?php $reduce_unwanted_colors = function (&$arr) use (&$reduce_unwanted_colors) { $rand_key = array_rand($arr); if ($arr[$rand_key] == 'blue') { return $arr; } else { unset($arr[$rand_key]); return $reduce_unwanted_colors($arr); } }; $arr = ['red', 'green', 'blue', 'orange', 'yellow']; print_r($reduce_unwanted_colors($arr));

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