PHP Transform mixed sequential and associative array to associative array

Question

I would like to build $goal array from $initial only. Any ideas? Thank you

Edit : the question could be how to differentiate associative parts from sequential ones.

$intial=[
    "one",
    "two"=>"myTwo",
    "three",
    "four"=>"myFour"
];
$goal=[
    "one"=>null,
    "two"=>"myTwo",
    "three"=>null,
    "four"=>"myFour"
];

Answer 1

The 'sequential' parts will have numeric keys, so if your 'associative' keys will always be strings, you could use that to differentiate:

$goal = [];
foreach ($initial as $key => $value) {
    if (is_numeric($key)) {
        $goal[$value] = null;
    } else {
        $goal[$key] = $value;
    }
}