Review language &  properties of trees
Ch15.1  Priority Queues
                Push items into a container...
                The Big lumps float to the top

        quote from standard<queue>
        sample demo code


        How the data sifts up the tree.
        Did you spot the mistake in the above two Images?

Ch15.2  Heaps
        A way to store a complete tree in a vector, array, or deque.

        demo/hands on
            draw tree, number nodes by levels 0.., plot into a vector

        quote from standard<algorithm> and sample test code
                and search (in page) for heap.

        STL vs book template
                STL does NOT define a heap<T> data type!
                Instead a couple of algorithms manipulate vectors

        15.2.1 -> adjust_heap algorithm
                ( Animation button at bottom.)

        bottom 369: use STL in project

        timing on p371

Also see

skip 15.3 Skew heaps - NO!

next 15.4 Prepare by studying the code for the icecream store.
Bring in your questions.
Be ready to use what you learned while studying this code.