php キーを用意して同じ値で連想配列を作成する

array_fill_keys( 配列, 値);

<?php

$arr =  [ "a", "b", "c", "d", "e" ];

$result = array_fill_keys( $arr, "mebee");

print_r($result);

Array
(
    [a] => mebee
    [b] => mebee
    [c] => mebee
    [d] => mebee
    [e] => mebee
)

<?php

$arr =  [ "a", "b", "c"];

$result = array_fill_keys( $arr, [1, 2]);

print_r($result);

Array
(
    [a] => Array
        (
            [0] => 1
            [1] => 2
        )

    [b] => Array
        (
            [0] => 1
            [1] => 2
        )

    [c] => Array
        (
            [0] => 1
            [1] => 2
        )

)

<?php

$arr = ["a" => 1, "b" => 2, "c" => 3];

$result = array_fill_keys( $arr, "mebee");

print_r($result);

Array
(
    [1] => mebee
    [2] => mebee
    [3] => mebee
)