[PHP] Problems in reference assignment in foreach loop

foreach($arr as &$value)
1. The reference assignment symbol & changes the current element into an address each time it loops. The $value variable is the address of the corresponding element. At the end of the loop, $value is An address pointing to the last element
2. When I loop next time and use this method foreach($arr as $value), there will be a problem; foreach will assign each element to the subsequent $value variable
3. Therefore, the logic becomes, modify each element to the last element of the original array, and the last loop will always be the result of the previous one.
4. It is best not to pass by reference, use this form $arr[$key]Change the original array, or change a variable name during the next loop

$nums=array(1,2,3);
foreach($nums as &$v){
        var_dump($v);
}
/*
int(1)
int(2)
int(3)
*/
var_dump($nums);
/*
array(3) {
  [0]=>
  int(1)
  [1]=>
  int(2)
  [2]=>
  &int(3)
}
*/
foreach($nums as $v){
        var_dump($v);
}
/*
int(1)
int(2)
int(2)
*/

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