从数值数组创建类似金字塔的数组

Question

My question is the following:

I'm looking tor an algorithm which makes $array1 look like $pyramid.

I Have this array:

$array1 = [
    'foo',
    'baz',
    'bar',
    'apple'
];

And I want to create a new array ($pyramid) from $array1 which looks like this:

$pyramid = [
    'foo' => [
        'baz' => [
            'bar' => [
                'apple' => ' '
            ]
        ]
    ]
];

The example $array1 has 4 elements, but it can be arbitrarily long, so the algorithm should work any dimension.

Answer 1

You mean something like:

$pyramid = [];
$pyramidPtr = &$pyramid;

foreach ($array1 as $element) {
    $pyramidPtr[$element] = null;
    $pyramidPtr = &$pyramidPtr[$element];
}
unset($pyramidPtr);

var_dump($pyramid);