CS Fall Homework 11 p. 1. CS Homework 11

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1 CS Fall Homework 11 p. 1 Deadline 11:59 pm on MONDAY, December 3, 2018 Purpose To practice with loops, arrays, and more! How to submit Submit your THREE.cpp FILES: CS Homework 11 hw11.cpp // containing your work for Problems 1, 2, 5, and 6 hw11-prob3.cpp hw11-prob4.cpp...for Homework 11 on the course Canvas site. (Remember, it is good to submit early and often!) Important notes While NetBeans is free software, and can run on Windows, Mac OS X, and Linux, it can be tricky to install. Be sure to leave yourself time to complete your homework in a campus lab if it turns out you have trouble with the NetBeans installation. You are still expected to follow the Design Recipe for all functions that you design/define. Remember, you will receive significant credit for the signature, purpose, header, and examples/tests portions of your functions. Typically you'll get at least half-credit for a correct signature, purpose, header, and examples/tests, even if your function body is not correct. (and, you'll lose at least half-credit if you omit these or do them poorly, even if your function body is correct). Be especially careful to include at least two examples/tests for every function, including at least one specific example/test for each "kind"/category of data, and (when there are boundaries) for boundaries between data. You can lose credit for not doing so. Be sure to follow class coding standards! Homework Program Setup For EACH of the THREE programs involved in this homework: (Remember, IF you are working in a campus lab, to log into your Google G: drive before starting up NetBeans. Look for the large ^ on the lower-right corner of your lab computer's screen Click on that, and click on the drive icon (with a triangular logo)...and log in.) Start NetBeans. From the File menu, select New Project....

2 CS Fall Homework 11 p. 2 You should see a screen that lets you select C/C++ as a Category and C/C++ Application as a Project. Do so, and click Next>. Type the desired project name in the Project Name box, and use Browse... to direct the Project Location folder to your desired location. (REMEMBER: in an HSU lab, this needs to be to the G: drive. On your own computer, you should be able to save your project wherever you would like.) Because you will be submitting.cpp files for THREE different programs for this homework, you WILL rename the.cpp file to have a name OTHER than main.cpp; the expected names are given in Problems 1, 3, and 4. All other options should remain as they are. Then select "Finish". In the left-side window, expand the Source Files section, then double-click on the.cpp file name you set this should open an editor window with the contents of that.cpp file. REPLACE its current contents with the "first main.cpp template" from the CS 111 public course web site, under "References". (You can REMOVE, or just not paste in, the very first "FIRST VERSION" comment.) See the comment that has by: and last modified:? START that comment with: CS HW 11 Then put your name after by:, and today's date after last modified:. For example: /*--- CS HW 11 by: Your Name last modified: */ Problem 1 Problems 1, 2, 5, and 6 will all be in a single NetBeans project; rename its main.cpp to be hw11.cpp. The purpose of this problem is to provide more loop practice, along with keeping track of a running total during a loop. Find the comment: /*--- PUT YOUR SIGNATURES, PURPOSES, and FUNCTION DEFINITIONS HERE ---*/ After this comment, type a blank link, and then type the comment: Problem 1 Recall that, in Homework 9, Problem 1, you wrote a function get_worth that expects a character representing a coin: 'Q' or 'q' -- quarter 'D' or 'd' -- dime 'N' or 'n' -- nickel

3 CS Fall Homework 11 p. 3 'C' or 'c' or 'P' or 'p' -- cent/penny...and it returns the decimal worth of that coin. paste in a COPY of your signature, purpose, tests (the ones in your opening comment), and function definition for get_worth after your Problem 1 comment. remember, if yours is not handy or you have any doubts about them, you may paste these from the posted Homework 9 example solutions. Also recall the string class method at, that expects the position of a desired character in that string, and returns the char at that position in the string (remembering, also, that it considers the position of the first character in the string to be position 0, not 1). Think about this -- Do you see that you could use a count-controlled loop with this at method to do something with each char within a string? (Hint: consider Week 12 Lecture 2's function vertical, that uses a countcontrolled loop and the at method to "grab" each character in a string and output it on its own line (thus outputting it in a "vertical" style).) Likewise, consider Week 12 Lecture 1's function sum_pos_ints, that shows how you can use a count-controlled loop to sum all of the integers from 1 to a given integer. NOW consider: what if you had a string whose characters were coin values? For example: "qdnncdqpn" Using the design recipe, write a function sum_worth that expects a string of coin characters, and returns the sum of the decimal worths of the coin characters in that string. For example, sum_worth("qdnncdqpn") == sum_worth("qn") == 0.30 For full credit, sum_worth must also: appropriately call and use get_worth appropriately use a loop Make sure you have at least the required number of tests for this function, and make sure you include them in the main function, also. Make sure sum_worth runs, and its tests pass! Problem 2 After Problem 1's sum_worth in hw11.cpp (before your main function), type a blank link, and then type the comment: Problem 2 For some more looping practice......consider -- what would you see on-screen if you called Week 14 Lab Exercise's function starline repeatedly? Remember, starline expects a desired number of stars/asterisks, has the side-effect of outputting a line of that many asterisks to the screen, and returns the number of asterisks printed to the screen.

4 CS Fall Homework 11 p. 4 paste in a COPY of your signature, purpose, tests (the ones in your opening comment), and function definition for starline after your Problem 2 comment. does your lab exercise partner have your pair's copy of starline, or do you have any doubts about your version? No problem -- there's an example solution posted on the course Canvas site, under "Week 14 Lab Exercise example solutions - in progress", that you can paste from. Using the design recipe, write a C++ function starbox that expects a desired number of rows and a desired number of asterisks per row, has the side-effect of printing to the screen that many rows of asterisks, each with that many asterisks per row, and returns the total number of asterisks printed out. This function must appropriately use a loop. This function must appropriately call starline. For example, starbox(3, 5) == 15 and has the side-effect of causing the following to be printed to the screen: * * * And, starbox(4, 2) == 8 and has the side-effect of causing the following to be printed to the screen: And, since starbox has side-effects, you should write tests for starbox in your main function that include a DESCRIPTION of what side-effects should be seen, along with the hoped-for true result from comparing the actually-returned value to the expected returned value. That is, for EACH of its examples/tests: it should first print a message saying that what follows should be a box of stars with <num> rows and <num> columns, followed by true, and then put that example/test in its own separate cout statement, such that the result of that test will be printed on its own line. Make sure starbox runs, and its tests pass! Problem 3 The purpose of this problem is to write a while loop that is NOT a count-controlled loop. What if you would like an interactive front end for a function that allowed the function to be called MORE than once? BUT instead of knowing how many times in advance it will go, you'd like to have it go as long as the user asks to continue. One way to do this is an approach that could be called a "question-controlled" loop. (That is, instead of being controlled by the value of a counter variable, it is controlled by a variable set by a user's answers to questions.) Consider Homework 9 - Problem 3's function pig_lite, which uses is_vowel, first, and rest, and which expects a word and returns a Pig-Latin-ish version of that word. An interactive front end for function pig_lite might be interesting, and perhaps a user would like the

5 CS Fall Homework 11 p. 5 option of "pig-litening" a number of different words. SO: Make a NEW NETBEANS PROJECT hw11_prob3, and rename its main.cpp to be hw11_prob3.cpp. This project will contain a program whose main function simply serves as an interactive front end for pig_lite, BUT allowing for the user to REPEATEDLY call pig_lite if they so choose. in project hw11_prob3's source file hw11_prob3.cpp, paste in COPIES of your signatures, purposes, tests (the ones in your opening comment), and function definitions for is_vowel, first, rest, and pig_lite before the main function. remember, if yours are not handy or you have any doubts about them, you may paste these from the posted Homework 9 example solutions. Now, since this is our first foray into question-controlled loops, below is pseudocode for such a loop. That is, in project hw11_prob3's main function, add code that does the following: Declare local variables to hold a user's answer and to hold an entered word to be piggified Ask the user to enter y if they would like to "piggify" a word Read in their answer while their answer is "y", ask the user to enter a word they'd like to see a Pig-Latinish version of read in the word they enter print to the screen, on its own line, the result of calling pig_lite on whatever the user entered ask the user to enter y if they would like to "piggify" ANOTHER word read in their answer Make sure this program runs successfully. Be sure to submit your hw11_prob3.cpp file for the project hw11_prob3! Problem 4 This problem's purpose is simply to serve an an array warm-up -- to allow you to try creating an example array and then do something with its contents. Make a NEW NETBEANS PROJECT hw11_prob4, and rename its main.cpp to be hw11_prob4.cpp. This project will contain a program consisting of JUST a main function! In this project's main function: decide on how big an array you would like -- any size larger than 5 is acceptable. Declare an appropriately-named named constant whose value is this size. decide what type of value you would like for your array to contain. declare an array of that type and size, and initialize it to values of your choice. then write a loop to do something to/with each value in your array.

6 CS Fall Homework 11 p. 6 You can choose -- it can be as simple as simply printing each value in the array, or something more elaborate (you can modify each value, call some function of your choice for each value, etc.) Whatever you choose, make sure it has some output/result printed to the screen. Make sure this program runs successfully. Be sure to submit your hw11_prob4.cpp file for the project hw11_prob4! Problem 5 The purpose of this problem is to write a function whose parameters include an array and its size. (Recall that you walked through such a function, sum_array, in Problem 3 of the Week 14 Lab Exercise.) BACK in your project hw11, BACK in your source file hw11.cpp that has your code for Problems 1 and 2, after Problem 2's starbox, (before your main function), type a blank link, and then type the comment: Problem 5 Consider, again, function starline, that expects the number of asterisks/stars to output, and it returns that number, but also has the side-effect of printing that many asterisks on one line to the screen (if <=0, no stars are output). You could use this to create a kind of horizontal bar chart, calling starline for each of a set of values. And what is an array but a set of values? Using the design recipe, write a C++ function bar_chart that expects an array of integers and its size, returns the number of rows in the resulting bar chart (that is, the array's size...!), and has the side-effect of printing to the screen a horizontal bar chart with the help of starline, printing a line of *'s the length of each array value. This function must appropriately call starline And, it must use an appropriate loop. For example, for: const int NUM_MSRS = 7; int measures[num_msrs] = {3, 1, 6, 2, 8, 4, 5}; bar_chart(measures, NUM_MSRS) == NUM_MSRS...and has the side-effect of causing the following to be printed to the screen: * * * Since bar_chart has side-effects, you should write tests for bar_chart in your main function that include a DESCRIPTION of what side-effects should be seen, along with the hoped-for true result from comparing the actually-returned value to the expected returned value. That is, for EACH of its examples/tests:

7 CS Fall Homework 11 p. 7 it should first print a message saying that what follows should rows of stars of lengths <list them>, followed by true, and then put that example/test in its own separate cout statement, such that the result of that test will be printed on its own line. Make sure bar_chart runs, and its tests pass! Problem 6 After Problem 5's bar_chart in hw11.cpp (before your main function), type a blank link, and then type the comment: Problem 6 The purpose of this problem is to write another function whose parameters include an array and its size. Using the design recipe, write a C++ function how_many that expects a desired string, an array of strings, and the array's size, and returns the number of times the desired string appears in that array. It is required to appropriately use a loop. (suggestion: during the design recipe, after making your specific examples/tests, develop pseudocode for how you figured out how many times your example string appeared in your example array -- how did you know when a match was found? how do you keep track of how many you've seen so far?) (hint: for this one there had better be more than one example call! What are the different cases you should check? But as an additional hint -- if you design it well, you can probably use the same example array for more than one example call. What should be different in those calls, then?) how_many does not have side-effects, but remember that, when you write its tests in your main function, you need to also declare and initialize at least one appropriate array to use as argument for its tests, also declaring a named constant for its size. and then you can put each example/test in its own separate cout statement, such that the result will be printed on its own line. Make sure how_many runs, and its tests pass! Be sure to submit your hw11.cpp file for the project hw11!