A6-Loopy Programs

Table of Contents


Objectives

  • Apply counting loops to display data
  • Use indefinite loops to process data
  • Develop the ability to find minimum and maximum values
  • Code nested loops

Academic Honesty

Read the Scholastic Honesty Policy and Assignment Integrity policies of the syllabus. Here are some clarifications for this particular assignment:

  • You are encouraged to work with one other student of this class following the rules of Pair Programming for Homework Assignments. If you choose to pair program, there is a bonus applied.
  • You may not give a copy of your code to your designated pair-programming partner if you did not develop the code together.
  • You may not show your completed code to another person or look at another person's code until you complete and submit this assignment, except for code you develop together with your pair-programming partner.
  • You may get help from people other than your pair-programming partner if you get stuck, but only if they do not show or tell you the code to type.
  • Remember that the instructor performs similarity tests on programming project submissions, and plagiarized code is usually very easy to detect.

Preparation

  1. Make sure you have completed the exercises from lesson 5 and lesson 6.
  2. Complete the Review Exercises in CodeLab 5 and 6. These exercises will help prepare you for the problem-solving programs and should be completed first.

Project Specifications

Your solutions to these projects must only use techniques we have covered so far.

Programming Style

For all programs, remember to follow all the style rules we covered including the recent items:

  1. No magic numbers
  2. Indentation in while statements and placement of curly braces
  3. No tab characters in your code.

    You can remove tab characters by either setting up TextPad correctly (see here) or by running a program named astyle (see here).

  4. Meaningful variable names and consistent naming style (caps vs. underbars).

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Image source (modified)

Project 1: Loop Worksheet

Counting loops are very commonly used in programming to ... count things. Character data types are used to store and display individual letters and other symbols. The string type stores sequences of characters. In this project we explore the relationships between counting loops, characters and strings in C++.

Project Specifications
  1. Start by downloading the worksheet: loopwork.cpp.

    Keep the same filename and add to the existing code to complete the project. Leave the existing code unchanged, except as explained with comments and these instructions. Include all your code in this single file.

  2. Add your name and the date to the file comment block at the top of the file.
  3. User input is already coded into the worksheet.

    Do not add any other input commands or change the input order.

  4. Read the comments in the worksheet file and write the code where indicated by the comments. See the Example Run to verify the correctness of each computation.
  5. Example Run: The input prompts and outputs of the program must look like the following for full credit, including the same order of input and exact wording of the output. For the input shown you must get the same output. However, the output must change properly if the inputs are different.
    *** Loop Worksheet! ***
    Enter a string message: Hello World!
    Enter a single character: e
    Enter an integer between 1 and 20: 3
    
    *** Printing the length of the string followed by an _ for 3 times ***
    #1: 12_12_12_
    That is the length followed by _ for 3 times
    
    *** Printing 3 x's alternating with + ***
    #2: x+x
    That's quite an alternation!
    
    *** #3: Printing the string 3 times ***
    -Hello World!
    -Hello World!
    -Hello World!
    Yay! We finished!
    
    *** Printing the string (Hello World!) in all upper case ***
    #4: HELLO WORLD!
    That makes a statement!
    
    *** Printing all the letters less than or equal to 'e' in the string ***
    #5:He--- W---d!
    Spotty printing!
    

    In the above example run, the user entered the values shown in aqua italics (for emphasis) to produce the output. Your program does NOT print the characters in aqua italics, nor does the user input appear in aqua italics.

  6. After displaying the output, exit the program.
  7. Submit the source code file loopwork.cpp with the rest of the assignment as described in Deliverables.
Hints:

Sticks lying on surface
Image credit

Project 2: A Game of Sticks

In the game of sticks there is a heap of sticks lying on a surface. It takes two players to play and the players decide how many sticks they want to start with.

After deciding on the number of sticks, the two players alternate turns.On their turn, each player picks up 1 to 3 sticks. The player who has to pick up the final stick is the loser.

The following is an example of the game of sticks.

  1. The game starts with 10 sticks on the board.
  2. Player Ed takes 3 sticks and 7 sticks remain.
  3. Player Hal takes 3 sticks and now 4 sticks remain.
  4. Player Ed takes 3 sticks and now 1 stick remains.
  5. Player Hal has to take the final stick and loses.

Since the game play repeats indefinitely, we use a loop to repeat the play while the number of sticks is greater than zero. Within the loop we alternate which player takes their turn. Once the game works we enclose the game within another loop to allow the players to repeat the game with the same number of sticks.

This project is adapted from the Stanford University Nifty Assignments, "Game of Sticks" [1].

Project Specifications
  1. Write a program for the game of sticks where two players can play against each other.
  2. Name the source code file sticks.cpp and include all your code in this single file.

    Be careful of the spelling, including capitalization, as you will lose points for a misspelled name. Naming is important in programming.

  3. When the game starts, ask for the number of sticks as shown in the Example Runs.
  4. Use a do or while loop that allows the game to continue by alternating between the two players, allowing each to pick up between 1 and 3 sticks as shown in the Example Runs.

    Assume that each player follows the rules because the other player is watching them.

  5. Game play repeats indefinitely until no sticks remain and the last player to pick up a stick loses.
  6. Before each play, show the number of sticks remaining using the message wording shown in the Example Runs.
  7. Add a second do or while loop that allows the user to repeat the game with the same number of sticks by entering a "1" (without the quotes) at the end of each game as shown in the Example Runs.
  8. Example Runs: The input prompts and outputs of the program must look like the following for full credit, including the same order of input and exact wording of the output. For the input shown you must get the same output. However, the output must change properly if the inputs are different.
    Welcome to the game of sticks!
    How many sticks to start with (10-100)? 10
    
    There are 10 sticks on the board.
    Player 1:How many sticks to take (1-3)? 3
    
    There are 7 sticks on the board.
    Player 2:How many sticks to take (1-3)? 3
    
    There are 4 sticks on the board.
    Player 1:How many sticks to take (1-3)? 3
    
    There are 1 sticks on the board.
    Player 2:How many sticks to take (1-3)? 1
    
    Player 2 loses.
    Play again (1 = yes, 0 = no)? 1
    
    There are 10 sticks on the board.
    Player 1:How many sticks to take (1-3)? 1
    
    There are 9 sticks on the board.
    Player 2:How many sticks to take (1-3)? 3
    
    There are 6 sticks on the board.
    Player 1:How many sticks to take (1-3)? 3
    
    There are 3 sticks on the board.
    Player 2:How many sticks to take (1-3)? 2
    
    There are 1 sticks on the board.
    Player 1:How many sticks to take (1-3)? 1
    
    Player 1 loses.
    Play again (1 = yes, 0 = no)? 0
    
    Welcome to the game of sticks!
    How many sticks to start with (10-100)? 12
    
    There are 12 sticks on the board.
    Player 1:How many sticks to take (1-3)? 3
    
    There are 9 sticks on the board.
    Player 2:How many sticks to take (1-3)? 2
    
    There are 7 sticks on the board.
    Player 1:How many sticks to take (1-3)? 3
    
    There are 4 sticks on the board.
    Player 2:How many sticks to take (1-3)? 3
    
    There are 1 sticks on the board.
    Player 1:How many sticks to take (1-3)? 1
    
    Player 1 loses.
    Play again (1 = yes, 0 = no)? 0
    

    In the above example runs, the users entered the values shown in aqua italics (for emphasis) to produce the output. Your program does NOT print the characters in aqua italics, nor does the user input appear in aqua italics. The values in (parentheses) are expected values when entering the example input.

  9. Add a do or while loop that allows the user to repeat the game with the same number of sticks by entering a "1" (without the quotes) at the end of each game as shown in the Example Runs.
  10. Submit the source code file sticks.cpp with the rest of the assignment as described in Deliverables.
Hints:
  • Do not use for-loops in this assignment.
  • Add the play again feature (spec 8) after the basic game works.
References and More Information
  1. Game of Sticks: from Stanford University Nifty Assignments

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Image source

Project 3: Real or Fake News Detector

Fake, or hoax, news websites deliberately publish made-up stories as news, using social media to drive web traffic and amplify their effect [1]. This is a form of dishonesty known as a scam or swindle, and has been a boon for people trying to make a quick profit. Profit for fake news sites is primarily driven by online advertising revenue made mostly through Facebook and Google [2]. Both Google and Facebook have announced measures to ban web sites that show illegal or misleading content [3][4][5]. Do NOT confuse fake news with opinionated analysis from sites made on the basis of their ideologies.

For this project you are to write a program to help identify fake (made up) news. The instructor is providing you with five (5) "news" samples from the internet for testing your program. Two (2) of the samples are fake news articles and three (3) are real news articles. You must decide which are fake and which are real and write your program to identify them correctly.

To prepare for the decision, try playing the game Factitious.

Project Specifications
  1. Write a program that scans a "news" article and decides if it is real or fake. The instructor will use the following articles for testing:
    1. children.txt
    2. ford.txt
    3. pharma.txt
    4. taxes.txt
    5. warming.txt
  2. The name of the source code file for this program must be realfake.cpp and all your code must be in this file.

    Be careful of the spelling, including capitalization, as you will lose points for a misspelled name. Naming is important in programming.

  3. Your program must run from the command line using redirection of input as follows:
    ./realfake < input.txt
    

    Where input.txt is the news article file to test. See lesson 6.1.5: Processing Text Input and Exercise 6.1: Finding Words for examples.

  4. Your program must print out a single word "Real" or "Fake" (without the quote marks) when run, depending on the article scanned, like this:
    ./realfake < input.txt
    Fake
    
  5. Your program must correctly output the word "Fake" on two (2) articles and "Real" on three (3) articles based on the contents of the articles.
  6. After printing the appropriate word, exit the program. Do NOT loop and run again.
  7. Submit this project with the rest of the assignment as described in Deliverables.
Hints:
  • Review lesson 6.1.5: Processing Text Input and choose a way to process text for your approach. Most students find comparing "words" easier like we did in Exercise 6.1: Finding Words.
  • Remember that "words" are any set of characters separated by spaces. Thus a word might include parenthesis like "(hello)".
  • Your final program should have a single while-loop and several if-statements inside the loop.
References
  1. Snopes' Field Guide to Fake News Sites and Hoax Purveyors
  2. Facebook and Google move to kick fake news sites off their ad networks
  3. Google Advertising Policies -- Misrepresentation
  4. Facebook -- Mark Zuckerberg Post 11/18/2016
  5. News Feed FYI: Addressing Hoaxes and Fake News (Facebook)
  6. An Update On Information Operations On Facebook
Resources

Here are some resources to help you get started solving the problem:

These sources may or may not correctly list fake news articles or sites. You must research and decide for yourself.

Extra Credit

The following are worth extra credit points:

  1. Complete the assignment using pair programming with the same person for all three projects. (2 points)
  2. Display fake and real for the actual fake and real news sites. (1 point)
  3. Play the extra credit game: Lightbot 1. (2 points)
    1. Requires flash installed and may not work on many browsers -- Chrome OK
    2. Complete the game through level 9
    3. Record the message shown at the beginning of level 10 in your README.txt under Extra Credit.
    4. Please do not cheat. If you get stuck, just explain how far you got in the README.txt and record the message for the level you completed.
    5. If you go beyond level 9, make certain to still record the message for the beginning of level 10.

Make certain that your README.txt file describes any extra credit attempted.

Tutorial Lab

In preparation for next weeks lessons, complete the following:

  1. Read the assigned reading in the textbook
  2. Complete the Tutorial Exercises in CodeLab 6 before the specified due date.

    Refer to the assigned reading for the next lesson to help you understand the problems. Also, you can use the online lecture notes for more information as the notes become available. You can look at solutions if you miss your first few attempts and are stuck by clicking the "Solution" tab.

Grading Criteria

The instructor will evaluate your assignment using the following criteria. Thus you should check your assignment against these criteria to maximize your score.

Each criteria represents a specific achievement of your assignment and has a scoring guide. The scoring guide explains the possible scores you can receive. Some scoring guides have a list of indicators. These indicators are a sign of meeting, or a symptom of not meeting, the specific criterion. Note that a single indicator may not always be reliable or appropriate in a given context. However, as a group, they show the condition of meeting the criterion.

For information on grading policies, including interpretation of scores, see the syllabus.

Lesson Exercises

  • 2: All lesson exercises attempted and turned in
  • 1: Some lesson exercises completed and turned in
  • 0: No lesson exercises completed or turned in

Programming Projects (x3)

  • 5: Demonstrates mastery of the program
    • Applies concepts from the lessons appropriately
    • Meets all specifications (see above)
    • Runs to completion with no abnormal error conditions
    • Generates correct output given correct input
    • Correct file name
  • 4: Has most of the functionality expected of the program
    • Demonstrates some techniques from the lesson
    • Attempts to meet all but one of the specifications (see above)
    • Implementation seems more complicated than necessary.
    • May have one minor error
  • 3: Has some of the functionality expected of the program
    • Demonstrates some techniques from the lesson
    • Attempts to meet at least 1/2 of the specifications (see above)
    • Implementation seems excessively complicated.
    • May have 2-3 minor errors
  • 2: Serious functional problems but shows some effort and understanding
    • Attempts to meet less than 1/2 of the of the specifications (see above)
    • Has a major error or many minor errors
    • Implementation seems very convoluted
    • Demonstrates few techniques from the lesson
  • 1: Does not compile or wrong file turned in
  • 0: Not turned in or uses techniques not covered

Programming Projects Style

  • 3: Code is well-documented including:
  • 2: Code has a minor documentation error
  • 1: Code has some documentation errors
  • 0: No apparent attempt to follow documentation standards or write documentation comments

CodeLab and Other Tutorial Exercises

  • Number CodeLab completed correctly / number exercises * 8 and rounded up to the nearest integer.

README.txt File

  • 2: README.txt file submitted following the instructions
  • 1: README.txt file submitted but some information was missing
  • 0: No README.txt file submitted

Total possible: 30, plus extra credit

Deliverables

Submit your assignment to Canvas, in the assignment folder A6-Loopy Programs, following the instructions for submitting homework. Include the following items for grading:

  1. README.txt file with option extra credit information
  2. All the exercise files from Lesson 5 and Lesson 6 including:
    • countdown.cpp
    • findword.cpp
    • forloop.cpp
    • scores.cpp
  3. loopwork.cpp
  4. sticks.cpp
  5. realfake.cpp

You must submit all the files needed to complete your assignment. Your assignment must work as submitted. Remember to test and double check your files before submitting them. If you make a mistake, you can resubmit up to the deadline. If you resubmit, you must include all your assignment files in the last submission as Canvas hides prior submissions.

Last Updated: October 15 2018 @21:50:55