====== Week 13 ======
~~NOTOC~~

===== Higher Order Functions / Midterm II (and Review) =====

==== Monday ====

  * Midterm Exam II this Friday
    * Gradescope: https://www.gradescope.com/
    * use your email address to login (same as for Midterm I)
    * this will be the //last// exam of the semester!
    * Review this Wednesday \\ \\

  * Lecture 15: Filter, Map, Fold
    * {{lecture15.pdf|PDF}}
    * {{ :courses:cs101-2021-5657:foldr.rkt |foldr.rkt}} \\ \\ 

  * Assignment 5: Simple Tetris
    * due: Mon, May 24, 11:59pm (last day of classes)
      * absolute deadline for all outstanding work: Thu, May 27, 11:59pm (end of Study Period)
    * demo and overview of starter code  \\ \\ 



==== Wednesday ====

**//Exam Promises for Midterm II//**

  * Handout(s): old exam(s)
    * Fall 2017 Midterm II {{ :courses:cs101-2021-5657:exam2.pdf |PDF}} (questions 2--5)
    * Spring 2019 Final Exam {{ :courses:cs101-2021-5657:final.pdf |PDF}} (question 2)
    * Solutions we worked through in class: {{ sample-exam2-sols.rkt }} \\ \\ 

  * Exam Promises for Midterm 2 
    * 75 points / 75 minutes
      * budget your time one point per minute
      * we actually have 120 minutes for our lab, and we can run over if needed (time will not be an issue)
    * Open book / open notes
      * you may access our textbook online
      * you may access any of our course pages online
      * you may open DrRacket for the purpose of viewing the lecture notes, labs, and assignments
      * //but// you may not run any programs, use the Stepper, or use the Interactions Pane in DrRacket--you're on your honor!
    * Exam is cumulative, but with an emphasis on the material covered since the first midterm
      * Lectures 7--14
      * HtDP/2e Parts:
        * II Arbitrarily Large Data
        * III Abstraction 
        * IV Intertwined Data
      * Topics: 
        * lists, list abbreviations
        * functions that consume lists, functions that consume multiple lists
        * binary trees (e.g., rumor mill, pipeline), and functions that consume them
        * intertwined data, mutually referential data definitions, mutually recursive functions (e.g. more realistic rumor mill, files and directories), and functions that consume intertwined data
        * abstracting over similar functions, higher order functions \\ \\
    * 5 questions, 15 points each 
    * **Q1** Russian Dolls question based on HtDP/2e [[https://htdp.org/2018-01-06/Book/part_two.html#%28part._rd._sec~3ard%29|Section 9.4]]
      * You will be asked to write a function that consumes a Russian Doll (RD). 
      * Even though this may seem to be something completely different, the Data Definition for a RD is really a thinly-veiled list! Design Recipe.
    * **Q2** Multiple Lists Function. You will be asked to write a function that consumes two lists. Based on Lecture 9, Multiple Complex Inputs. I'll even promise you it will be of the second variety (''parallel-sum'' was an example of this variety).
      * The question I ask you to write will be a variation of the question on the sample test.
    * **Q3** Binary Tree Function. I provide the data definition, you write the function. Design Recipe.
      * I will even promise you it will be the same definition of a binary tree as on the sample test, but...
      * The function I will ask you to write will be different.
    * **Q4** Function based on intertwined data: This question will be based on the data definitions for Files and Directories, from Lecture 12. I provide the data definition, you write the function(s). Recall: for intertwined data, when you are asked to write a function, you actually write multiple functions, one for each data definition. Design Recipe.
      * Again, the function(s) I ask you to write will be a variation of the function on the sample test. 
    * **Q5** Abstraction over and parameterizing similar functions. I will give you two very similar functions (like ''big'' and ''huge'' were similar in Lecture 14). This question will be very similar to Question 2 from the sample final exam (but not including the last part involving a ''lambda'' expression). 
==== Friday ====

  * Midterm II