Analyse der Methode zum Konvertieren eines Arrays vertikal in horizontal und zum Filtern doppelter Werte in PHP

array(
  6=>array(5=>'黑xx', 42=>'XXL'),
  7=>array(5=>'黑xx', 40=>'XL'),
  8=>array(8=>'灰',  40=>'XL'),
);

array(
  0=>array(5=>'黑xx', 8=>'灰'),
  1=>array(42=>'XXL', 40=>'XL'),
);

$a = array(
  6=>array(5=>'黑xx', 42=>'XXL'),
  7=>array(5=>'黑xx', 40=>'XL'),
  8=>array(8=>'灰',  40=>'XL'),
);
foreach($a as $r) {
 $b[key($r)] = current($r);
 next($r);
 $c[key($r)] = current($r);
}
$b = array($b, $c);
print_r($b);

$arr = array(
  6=>array(5=>'黑xx', 42=>'XXL'),
  7=>array(5=>'黑xx', 40=>'XL'),
  8=>array(8=>'灰',  40=>'XL'),
);
$result = array();
foreach($arr as $a){
  $keys = array_keys($a);
  $vals = array_values($a);
  $result[0][$keys[0]] = $vals[0];
  $result[1][$keys[1]] = $vals[1];
}
print_r($result);

$a = array(
  6=>array(5=>'黑xx', 42=>'XXL'),
  7=>array(5=>'黑xx', 40=>'XL'),
  8=>array(8=>'灰',  40=>'XL'),
);
foreach($a as $r) {
 $i = 0;
 while(list($k, $v) = each($r)) $b[$i++][$k] = $v;
}
print_r($b);

Array
(
  [0] => Array
    (
      [5] => 黑xx
      [8] => 灰
    )
  [1] => Array
    (
      [42] => XXL
      [40] => XL
    )
)