• Built in procedures like output, print, repeat, sum, product, word, first, butlast, and readlist
• Writing your own procedures
• Finding errors in procedures
• Plumbing diagrams
• Drawing using forward, right, left, penup, pendown, home
• Variables: as input, with subprocedures, and using make
• Predicates like numberp, equalp, lessp, and, and not
• Conditionals (if, ifelse)
• The commands for, while and map
• Recursion

Here is a link to the Fall 2009 Midterm and some Solutions. Some questions will have more than one correct answer.

Sample Exam Questions

1. Draw a plumbing diagram for the instruction:

   print product sum 2 3 7

2. Suppose the following procedures are defined:

   to silly :name
    nonsense first :name
    foolish last :name
   end
   
   to nonsense :word
    print sentence :word [had a little lamb.]
   end
   
   to foolish :word
    print sentence :word [is the loneliest number.]
   end
   

   What is the result of entering the instruction:

   silly [Heidi Louise Burgiel]

3. Write a procedure rectangle that takes two inputs -- a length and a width -- and draws a rectangle with the given length and width.
4. Write a predicate directionp that takes one input and outputs true if the input is one of the letters N, S, E or W and otherwise outputs false.
5. What is the result of entering the instruction:

   for [i 1 15 2] [print :i]

6. What is the result of entering the instruction:

   print map "numberp [Heidi Louise Burgiel]

7. Write a procedure that takes a positive integer n as input and outputs the sum 1² + 2² + 3² + ... + n².
8. The procedure sumup defined below was supposed to add the numbers from 1 to the input :n. Instead, it gives the error message shown. Why?

   ? to sumup :n
   > if equalp :n 0 [stop]
   > output :n + sumup :n-1
   > end
   sumup defined
   ? sumup 3
   sumup didn't output to + in sumup
   [output :n + sumup :n-1]