unset array key and rearrange the key - php

Question

This is how my array looks like :
Array
(
[0] => Array
(
[unit] => 10
[harga] => 15000
)
[1] => Array
(
[unit] => 7
[harga] => 10000
)
[2] => Array
(
[unit] => 12
[harga] => 123123
)
)
I want to unset the 0 key array when the unit is 0 and rearrange the key so the 1 key will replace the 0.
This is how I do it :
$jumlah_penjualan = $data - > unit;
while ($jumlah_penjualan > 0) {
$persediaan_pertama = $persediaan[0]['unit'];
$harga_persediaan = $persediaan[0]['harga'];
if ($persediaan_pertama < $jumlah_penjualan) {
$dijual = $persediaan_pertama;
$penjualan[] = array(
'unit' => $dijual,
'harga' => $harga_persediaan,
'total' => $dijual * $harga_persediaan);
$persediaan[0]['unit'] = $persediaan[0]['unit'] - $dijual;
} else {
$dijual = $jumlah_penjualan;
$penjualan[] = array(
'unit' => $dijual,
'harga' => $harga_persediaan,
'total' => $dijual * $harga_persediaan);
$persediaan[0]['unit'] = $persediaan[0]['unit'] - $dijual;
}
if ($persediaan[0]['unit'] == 0) {
unset($persediaan[0]);
$persediaan = array_values($persediaan);
}
$jumlah_penjualan = $jumlah_penjualan - $dijual;
}
But the result looks like it continues looping before rearranging the array.
This is how the array should look like after unset:
Array(
[0] => Array
(
[unit] => 9
[harga] => 123123
)
)

Answer 1

If you want to remove the first elements until the unit is not 0, you can
$arr = array
(
array
(
"unit" => 0,
"harga" => 15000
),
array
(
"unit" => 0,
"harga" => 10000
),
array
(
"unit" => 12,
"harga" => 123123
)
);
while( $arr[0]["unit"] == 0 ) { //Loop until $arr[0]["unit"] is not 0
unset($arr[0]); //Remove $arr[0] since unit is 0
$arr = array_values($arr); //Make Make element 1 to element 0
}
echo "<pre>";
print_r( $arr );
echo "</pre>";
This will result to:
Array
(
[0] => Array
(
[unit] => 12
[harga] => 123123
)
)

Answer 2

To remove the first element of an array and reindex the elements, use array_shift. First, check that the number of units are zero, then remove the first element if that's the case.
if ($arr[0]['unit'] == 0) {
array_shift($arr);
}
Since it's impossible to say what your other variables even mean because of the language, you probably want to move this outside of your while loop, so that the first element is only removed after you've processed the array.