php Example #6 Keys not on all elements

Example #6 Keys not on all elements

<?php
$array = array(
         "a",
         "b",
    6 => "c",
         "d",
);var_dump($array);?>

The above example will output:

array(4) {
  [0]=>
  string(1) "a"
  [1]=>
  string(1) "b"
  [6]=>
  string(1) "c"
  [7]=>
  string(1) "d"
}

As you can see the last value "d" was assigned the key 7. This is because the largest integer key before that was 6.