CSC151.02 2016S, Review Session 14 (2016-05-12)
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**No one showed up.  All you get are my preliminary notes.**

_Overview_

* About the final
* Sample final problems
* Other questions

About the final
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* In class.
* Thursday, 9-noon (alternate: Wednesday, 2-5pm.)
* Somewhat like a big quiz (no computers).
* Four questions.  
* Typical forms of questions
    * Write code
    * Read code and give sample output
    * Analyze efficiency
* Cumulative, but likely to focus more on end-of-semester issues.
* Simple grading scheme.
    * Four right or mostly right: A
    * Three right or mostly right: B
    * Two right or mostly right: C
    * One right or mostly right: D
    * Zero right or mostly right: F
* You may bring one sheet of notes.  
  (8.5"x11" or A4, double sided, hand-written).

Problem 1: Is it sorted?
------------------------

Key idea: Use vector recursion.

    (define vector-proc
      (lambda (vec)
        (let kernel ([pos 0])
          (cond
            [(= pos (vector-length vec)) ; Or something similar
             base-value]
            [(another-test)
             base-value]
            [else
             (kernel (+ pos 1))]))))

We are returning a Boolean.

What should our base values be?

Problem 2: Whatzitdo?
---------------------

We've seen something similar on an exam (or at least I think we have).

Problem 3: Is it efficient?
---------------------------

We know that `append` requires 1 call to cons for each value in the first
list.

So, to reverse a list of length `n` using `list-reverse-1` ...

* append n-1 elements and build a list of 1 element: n calls to cons
* append n-2 elements and build a list of 1 element: n-1 calls to cons
* ...
* apppend 1 element and build a list of 1 element: 2 calls to cons
* append 0 elements and build a list of 1 element: 1 call to cons

So 1+2+3+...+n, which we now know is n(n+1)/2.

Alternately, you could work out the steps by hand.

Problem 4: Nesting
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Other Questions
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_There were none._