I want only first array non empty index with second array with same index, meaning just in this case replace first array index 0 with second array index 0: 

```
$all_images => array:2 [ 0 => "00fb319e3af47a5600d39248ad5ea9c2.png"

                         1 => null ]

$images => array:2 [ 0 => "1508159073atouch-q12-tablet-new-white-color-27-09-2017.png"

                     1 => "1508159073atouch-q12-tablet-new-white-color-30-07-2017.png" ]

```

The result:

```
$New_images => array:2 [ 0 => "00fb319e3af47a5600d39248ad5ea9c2.png"

                         1 => "1508159073atouch-q12-tablet-new-white-color-30-07-2017.png" ] 

```