PHP | AppendIterator next() Function

<?php
 
// Declare an ArrayIterator
$arr1 = new ArrayIterator(array('G', 'e', 'e', 'k', 's'));
 
// Create a new AppendIterator
$itr = new AppendIterator;
 
// Append the ArrayIterator element
$itr->append($arr1);
 
// Display the current element of iterator
var_dump($itr->current());
 
// Use AppendIterator::next() function to
// move into next element
$itr->next();
 
// Display the current element of iterator
var_dump($itr->current());
 
?>

<?php
 
// Declare an ArrayIterator
$arr1 = new ArrayIterator(
    array(
        "a" => "Geeks",
        "b" => "for",
        "c" => "Geeks"
    )
);
 
$arr2 = new ArrayIterator(
    array(
        "x" => "Computer",
        "y" => "Science",
        "z" => "Portal"
    )
);
 
// Create a new AppendIterator
$itr = new AppendIterator;
$itr->append($arr1);
$itr->append($arr2);
 
$itr->rewind();
 
while ($itr->valid()) {
    echo "ArrayIterator Key: " . $itr->key() .
    "  ArrayIterator Value: " . $itr->current() . "\n";
     
    $itr->next();
}
 
?>