Prerequisites: Read all chapters through Chapter 4 in the textbook before attempting this lab. Read through this entire assignment before you begin.

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Assignment Number 5 Lab Assignment Due Date: Wednesday, October 3, 2018 LAB QUESTIONS Due Date: Email before Monday, October 8, 2018 before 5:00 PM CS 1057 C Programming - Fall 2018 Purpose: write a

1 Assignment Number 5 Lab Assignment Due Date: Wednesday, October 3, 2018 LAB QUESTIONS Due Date: before Monday, October 8, 2018 before 5:00 PM CS 1057 C Programming - Fall 2018 Purpose: write a complete program to perform multiple calculations use an IF statement create your own functions to break a complicated problem into smaller, manageable, pieces prove you understand how functions communicate Prerequisites: Read all chapters through Chapter 4 in the textbook before attempting this lab. Read through this entire assignment before you begin. Problem Specification: Create a program to process cash change using standard U.S. denominations of pennies, nickels, dimes, quarters, dollar bills, five-dollar bills, tens, and twenties. Figure out how many of each bill or coin that you expect to get back for a given amount. For example, if you need to give back $3.87 in change, you would have 3 one-dollar bills 3 quarters 1 dime 2 pennies The Fun Twist! Sometimes, you don't have all the denominations available in your cash drawer a shortage of one of the denominations! Write your program to allow for being out of a denomination or multiple denominations: dimes, for example. In that case, the $3.87 ends up being 3 ones, 3 quarters, 2 nickels and 2 pennies.

Tasks: 1) Use the function you created in the previous lab assignment to output the program tag line when it starts running. Adjust it by editing the source code for this program.

Repeat as necessary. DO NOT try and write this entire program all at once. First Part You should be able to do this first part without using any IF statements.

2 Tasks: 1) Use the function you created in the previous lab assignment to output the program tag line when it starts running. Adjust it by editing the source code for this program. In the future, we'll use the inputs to avoid changing the C code, but for this one, just edit it. 2) This program MUST be written in small steps. Write some code, compile, and test run. Repeat as necessary. DO NOT try and write this entire program all at once. First Part You should be able to do this first part without using any IF statements. If you're using IFs here, you're doing it incorrectly. Create a source code file called lab5.c. Write your program to handle the situation where there is no shortage and you have all the coins and bills available. Create a function to prompt the user to enter an amount. This function should be named prompt_user_for_amount( ). Create another function called calculate_change( ), which takes one input parameter, the amount of money needed to give back, and then one output parameter for each of the eight denominations, giving 9 parameters in total. Then write a function to print the results, print_change( ), with the eight denominations as parameters. Validate your program works by running it (and scripting the output) with the following amounts: 1) ) ) ) ) Save the script, and this version of your program, to separate files. Mail them together with the next part.

Second Part Copy your source code to a new file to modify. cp lab5.c lab5_part2.c Create a function to prompt the user to ask for shortages, after the user enters the amount.

3 Second Part Copy your source code to a new file to modify. cp lab5.c lab5_part2.c Create a function to prompt the user to ask for shortages, after the user enters the amount. This should be a separate function, called prompt_for_shortages( ), that takes a string to use for a prompt and returns the one that's missing, using the symbolic constants below. The prototype should look like the following: int prompt_for_shortages( char *prompt ); You will need to invoke this function three times, giving the user an opportunity to identify which denomination is missing. We will use the following codes to represent the various denominations in the program, and these codes are what the function prompt_for_shortages( ) will return. If there are no missing denominations, all three of these return parameters will be NO_MISSING. #define NO_MISSING 0 #define MISSING_PENNIES 1 #define MISSING_NICKELS 2 #define MISSING_DIMES 3 #define MISSING_QUARTERS 4 #define MISSING_DOLLARS 5 #define MISSING_FIVES 6 #define MISSING_TENS 7 #define MISSING_TWENTIES 8 Now you can add IF statements to the program, to check to see if any given denominations are missing. To make sure your program is working correctly, create a script of the output using the same values from the first part above, but this time, eliminate 1) dollars and dimes 2) fives, dimes, and nickels 3) twenties and pennies

4 Helpful Hints: DESK CHECK You should desk check your algorithm to insure you know what's happening at all points in your program.walk through you code line by line and confirm you're doing the math you think you're doing. ROUNDING HURTS DOUBLES AND FLOATS Floating point numbers are subject to rounding, which could hurt your ability to accurately count the pennies in your program. Consider using INTs for all calculations to avoid rounding issues. INERACTIVE PROMPTING Make sure your prompting the user clearly for what input you need. ECHO PRINT You should echo print your input to confirm you're reading in what you think you're reading in. PRINT CALCULATIONS You may want to display your in-progress calculations when writing your program, to make sure you're calculating the values correctly. SAVE YOUR WORK Once the program works correctly, be sure to make a COPY of your work on a flash drive or by ing your code to another computer. Remember: You are responsible for keeping copies of your code. NOTE: The final version of your code may still print out the intermediate calculations, just to show all of your work to the lab instructor.

5 Questions: Answer the following questions about the source code above. Bring the answers to class on the due date to discuss. your answers to before the due date and time. 1. Explain what is meant by short-circuit evaluation. Where would you use this? 2. Why are compound statements useful in C IF statements? 3. What would the limitations be on programming if we didn't have control structures? 4. Explain the difference between a condition and a logical expression. 5. How does the compiler differentiate between a unary operator and a binary operator when used in a C statement like the following Explain your answer. computed = 7 * - n How does the compiler calculate the following condition? Explain your answer. if ( alpha beta && gamma ) 7. Explain the difference between "A" and 'A' in C source code. 8. Explain in 30 words or less what makes a cohesive function? 9. The following C code checks if color is 4 and if the size is 2, 4, or 6, but it doesn't work. Why? int size = 4; int color = 9; if ( color == 4 length == 2 == 4 == 6 ) { puts( "The size and color are correct!" ); }

6 10. Given the following: printf( "Enter your age in years: " ); scanf( "%d", &age_in_years ); int is_voting_age = ( age_in_years >= 18 ); int is_drinking_age = ( age_in_years >= 21 ); int can_be_president = ( age_in_years >= 35 ); int is_senior_citizen = ( age_in_years >= 65 ); a) When the age entered is 33, what are the values of the variables above? b) When the age entered is 12, what are the values of the variables above? c) Write an IF statement in a function to print 'Yes' for each value above that is true. 11. What is pseudocode? Explain where you might use it. 12. Write an expression to test for each of the following relationships: a. age is from 18 to 21, inclusive. b. water_temperature is less 92.7 but greater than c. year is divisible by 4. d. speed is not greater than 55. e. x is greater than y but not larger than c. f. w is not equal to 3, 6, or 10, and less than maximum. 13. Complete programming problems 1 through 4 on page of the textbook.

7 Grade Calculation: 20% - Code compiles without errors 40% - Code is properly commented and indented, uses step-by-step calculations, not one big calculation, with functions commented as documented on the web site and including appropriate names for the variables 20% - Script file is included and shows all input and output performed by the program 20% - Code runs correctly and generated correct output For each day the lab is late, 5% will be taken off. Note: The questions are graded separately and count towards the classroom participation grade.

Instructions PLEASE READ (notice bold and underlined phrases)

Instructions PLEASE READ (notice bold and underlined phrases) Assignment 2 Writing Basic Java Programs Required Reading Java Foundations Chapter 2 Data and Expressions Chapter 3 Sections 3.1-3.2, 3.4-3.7 Chapter 4 Sections 4.2-4.5, 4.7-4.8 Instructions PLEASE READ