CS 3190 Programming Language Workshop in Scala (1 Credit)

· Office Hrs : TTh, 11:15am-12:15pm , 395 Joshi (or by appointment)

· One and Only Meeting (Attendance Optional): September 6, Wednesday, 11:30am-12pm, 399 Joshi

Course Description

This course is designed as a self-study in Scala. You are expected to learn the language and solve a set of programming problems assigned to you using Scala available from http://www.scala-lang.org/. There are no exams. We officially meet only once in the semester (and attending this meeting is optional if the online document is clear). However, I will be available in the posted office hours for clarifications and discussions about the programming problems. Typically, most of the comunication is via  emails.

Prerequisite

Reference Texts

Grading

Each programming assignment will be graded as Pass/Unsatisfactory, and the letter grade 'P' or 'U' will be assigned at the end of the course.

Course Policies

  1. All work must be turned-in by December 08, 2017. 
  2. Do not expect an incomplete for any reason. Each assignment has separate deadlines.
  3. You must pass all the assignments to pass the course. The code you turnin must be your own creation. Copying code from available books, and/or cutting and pasting code from the Internet is strictly prohibited.
  4. Each program should be well-documented and adequately tested.
  5. You must turnin well-documented source code runnable using Scala. You should include (i) instructions for running and testing the program,  and (ii) sample test inputs and outputs to indicate that you have tested your code adequately, in the source file as comments or as a separate ReadMe.txt . If you have multiple files, submit them as a single zip-archive. To turnin the ith assignment (where i = 1,2,...), create asgi.scala or the archive asgi.zip, and upload it to the corresponding assignment DropBox on Pilot before or on the due date.
  6. You may also be required to demonstrate your code in my office hours after the due date.

Assignments

(Assignment 1 - due 09/18)  Gray Code Generation

An n-bit Gray code is a sequence of n-bit strings constructed according to certain rules. For example,
    n = 1: C(1) = ("0", "1").
    n = 2: C(2) = ("00", "01", "11", "10").
    n = 3: C(3) = ("000", "001", "011", "010", "110", "111", "101", "100").
Find out the construction rules and write a function to generate Gray codes. 
scala> gray(3)
res0 : List[String] = List(000, 001, 011, 010, 110, 111, 101, 100)
(Assignment 2 - due 10/16)  Random walk problem 
1) A classic problem in statistics is the random walk. Imagine a drunken man standing on the center square of a sidewalk consisting of 11 squares. At each step, the drunk can elect to go right or left. How long will it be until he reaches the end of the sidewalk, and how many times will he have stood on each square? To solve the problem, represent the number of times the drunk has stood on a square as an array, and use  random number generating function for simulation. Display the value of the array at the beginning, at the end, and a few intermediate steps. (Make the latter programmable by defining a constant increment at the beginning of the program.)

(2) Now repeat the same for a two-dimensional variation on the random walk using an 11-by-11 array, and four moves: up, down, left, and right.
(Assignment 3 - due 11/13) Encrypting Messages + Verbalizing numbers in English. 
(1) In this exercise,  we explore cyclic cipher to encrypt messages. This type of cipher was used by Julius Caesar to communicate with his generals. It is very simple to generate and can be easily broken. The key idea behind the Caesar cipher is to replace each letter by a letter some fixed number of positions down the alphabet. For example, if we want to create a cipher shifting by 3, you will get the following mapping:
Plain: ABCDEFGHIJKLMNOPQRSTUVWXYZ
Cipher: DEFGHIJKLMNOPQRSTUVWXYZABC
Write a program that takes a string and a shift value to generate the Cipher.  Read up and check out  ROT13, an invertible cipher.
(2) On financial documents, like cheques, numbers must sometimes be written in full words. For example: 175 must be written as 'one hundred and seventy five'. Write a function verbalize(num: Int) to print (non-negative) integer numbers in words.
scala> verbalize(0)
res3: String = zero
scala> verbalize(1234567890)
res4: String = one billion two hundred and thirty four million five hundred and sixty seven thousand eight hundred and ninety
scala> verbalize(1000020345)
res5: String = one billion twenty thousand three hundred and forty five
(Assignment 4 - due 12/08) Open Ended Problem. 
Take a non-trivial Java application (say 150-200 lines of code in OOP style) that interests you and rewrite it in Scala. Turnin both the versions. Document and critique the generic changes to be made to the Java program to obtain the corresponding Scala program and the resulting reduction in code size in ReadMe.txt.