PHP -处理重复的数组键(内部指针)

$array = array(1, 2, 2, 3, 4, 4);
$uniqueArray = array_unique($array);
print_r($uniqueArray);

Array
(
    [0] => 1
    [1] => 2
    [3] => 3
    [4] => 4
)

$array = array(1, 2, 2, 3, 4, 4);
$flippedArray = array_flip($array);
$uniqueArray = array_values($flippedArray);
print_r($uniqueArray);

Array
(
    [0] => 1
    [1] => 2
    [2] => 3
    [3] => 4
)

$array = array(1, 2, 2, 3, 4, 4);
$uniqueArray = array();
foreach ($array as $value) {
    if (!in_array($value, $uniqueArray)) {
        $uniqueArray[] = $value;
    }
}
print_r($uniqueArray);

Array
(
    [0] => 1
    [1] => 2
    [2] => 3
    [3] => 4
)