Method 'next' deletes node from top. See example: <?php$queue = new SplPriorityQueue();$queue->insert('Q', 5);$queue->insert('W', 1);$queue->insert('E', 4);$queue->insert('R', 2);$queue->insert('Y', 3);$queue->next();$queue->next();$queue->next();print_r($queue);?>Will be output:SplPriorityQueue Object( [flags:SplPriorityQueue:private] => 1 [isCorrupted:SplPriorityQueue:private] => [heap:SplPriorityQueue:private] => Array ( [0] => Array ( [data] => R [priority] => 2 ) [1] => Array ( [data] => W [priority] => 1 ) ))