doubly linked list node doubly linked list append operation delete operation list search circular lists appending elements deleting an element iterating through circular list summary stacks and queues stacks stack implementation push operation pop operation peek bracket-matching application queues list-based queue enqueue operation dequeue operation stack-based queue enqueue operation dequeue operation node-based queue queue class enqueue operation dequeue operation application of queues media player queue summary trees terminology tree nodes binary trees binary search trees binary search tree implementation binary search tree operations finding the minimum and maximum nodes iii