CMU 15-112 Summer 2018: Fundamentals of Programming and Computer Science
Homework 5 (Due Wed 11-Jul, at 5pm)

• This assignment is SOLO. This means you may not look at other student's code or let other students look at your code for these problems. See the syllabus for details.


• To start:
  1. Download hw5.py to your 'week2' folder
  2. Edit hw5.py using Pyzo
  3. When you are ready, submit hw5.py to Autolab. For this hw, you may submit up to 10 times, which is fewer times than you've had in the past but only your last submission counts.
  4. You will have fewer test cases given to you this time around.
• Do not use sets, dictionaries, or recursion in this assignment.
• Do not hardcode the test cases in your solutions.

1. lookAndSay(a) [25 pts]
   First, read about look-and-say numbers here. Then, write the function lookAndSay(a) that takes a list of numbers and returns a list of numbers that results from "reading off" the initial list using the look-and-say method, using tuples for each (count, value) pair. For example:

     lookAndSay([]) == []
     lookAndSay([1,1,1]) == [(3,1)]
     lookAndSay([-1,2,7]) == [(1,-1),(1,2),(1,7)]
     lookAndSay([3,3,8,-10,-10,-10]) == [(2,3),(1,8),(3,-10)]
   



2. inverseLookAndSay(a) [25 pts]
   Write the function inverseLookAndSay(a) that does the inverse of the previous problem, so that, in general:

     inverseLookAndSay(lookAndSay(a)) == a
   

   Or, in particular:

     inverseLookAndSay([(2,3),(1,8),(3,-10)]) == [3,3,8,-10,-10,-10]
   

   
   
3. bestScrabbleScore(dictionary, letterScores, hand) [50 pts]
   Background: In a Scrabble-like game, players each have a hand, which is a list of lowercase letters. There is also a dictionary, which is a list of legal words (all in lowercase letters). And there is a list of letterScores, which is length 26, where letterScores[i] contains the point value for the ith character in the alphabet (so letterScores[0] contains the point value for 'a'). Players can use some or all of the tiles in their hand and arrange them in any order to form words. The point value for a word is 0 if it is not in the dictionary, otherwise it is the sum of the point values of each letter in the word, according to the letterScores list (pretty much as it works in actual Scrabble).
   
   In case you are interested, here is a list of the actual letterScores for Scrabble:

      letterScores = [
      #  a, b, c, d, e, f, g, h, i, j, k, l, m
         1, 3, 3, 2, 1, 4, 2, 4, 1, 8, 5, 1, 3,
      #  n, o, p, q, r, s, t, u, v, w, x, y, z
         1, 1, 3,10, 1, 1, 1, 1, 4, 4, 8, 4,10
      ]
   

   Note that your function must work for any list of letterScores as is provided by the caller.
   
   With this in mind, write the function bestScrabbleScore(dictionary, letterScores, hand) that takes 3 lists -- dictionary (a list of lowercase words), letterScores (a list of 26 integers), and hand (a list of lowercase characters) -- and returns a tuple of the highest-scoring word in the dictionary that can be formed by some arrangement of some subset of letters in the hand, followed by its score. In the case of a tie, the first element of the tuple should instead be a list of all such words in the order they appear in the dictionary. If no such words exist, return None.
   
   Note: there is no fixed dictionary here. Each time we call the function, we may provide a different dictionary! It may contain 100 words or perhaps 100,000 words.

Bonus

See hw5-bonus linked on the schedule page!