PHP - 在第一个之后获取所有密钥

From an array in PHP for example:

array(
    [0] => "A",
    [1] => "B",
    [2] => "C",
    [3] => "D"
)

How can I get an array containing the keys after the fisrt one. So the example will be:

array(
    [0] => "B",
    [1] => "C",
    [2] => "D"
)

array_shift is a possibility.

$output = array_shift($input);

array_slice() is one way:

$result = array_slice($array, 1);

array_slice returns a subsequence of an array.

array_slice($array, 1);

array_shift($array);

array_shift modifies the array as a reference. If you need the value that is shifted, simply assign it to a variable.

DEMO