Foreach Reference Trap
<?php
$array = [1,2,3,4,5];
foreach($array as &$value){
$value *= 2;
}
<!-- So this reference will change the main array to [2,4,6,8,10] -->
<!-- But before of the below logic or code we need to unset the $value otherwise if I add $value = 100 then last element value will be change 10 to 100. -->
unset($value);
<!-- try to substruct from each element from updated array -->
$result = array_map(fn($element) => $element - 1, $array);
echo implode(', ', $result);