how to separate array first key from rest of the keys from array using PHP?

one text

Solution:

$arr = [
   ['a','b','c'],
   ['a1','b1','c1']
];

$newArray = [];

foreach ($arr as $key => $data) {
    $newKey = $data[0];
    unset($data[0]);
    $newArray[$newKey] = $data;
}

print_r($newArray);

output:

Array
(
    [a] => Array
    (
        [1] => b
        [2] => c
    )

    [a1] => Array
    (
        [1] => b1
        [2] => c1
    )

)

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