Question

Perform each of these steps: a. Read the problem statement. b. Formulate the algorithm using pseudocode and top-down, stepwise refinement. c. Write a \(C++\) program. d. Test, debug and execute the \(C++\) program. Drivers are concerned with the mileage obtained by their automobiles. One driver has kept track of several tankfuls of gasoline by recording miles driven and gallons used for each tankful. Develop a \(C++\) program that uses a while statement to input the miles driven and gallons used for each tankful. The program should calculate and display the miles per gallon obtained for each tankful and print the combined miles per gallon obtained for all tankfuls up to this point.

Short answer

Create a C++ program to calculate MPG using a loop and basic arithmetic operations; test thoroughly.

Step-by-step solution

Understand the Problem

The problem requires us to create a C++ program that calculates and displays the mileage information for multiple tankfuls of gasoline consumed by a driver. Specifically, it requires calculating the miles per gallon (MPG) for each tankful and the cumulative MPG for all tankfuls recorded. Input will be the miles driven and gallons used for each entry until the user decides to stop.

Algorithm in Pseudocode

Let's formulate the algorithm using pseudocode with stepwise refinement. Pseudocode: 1. Initialize variables: - totalMiles = 0 - totalGallons = 0 2. While more tankfuls exist: - Input miles and gallons for the current tankful - Calculate Tankful MPG = miles/gallons - Display Tankful MPG - Update totalMiles and totalGallons - Calculate cumulative MPG = totalMiles/totalGallons - Display cumulative MPG 3. End program when the user indicates no more input.

C++ Program Writing

Here's the C++ code implementation based on the pseudocode: ```cpp #include using namespace std; int main() { double miles, gallons; double totalMiles = 0, totalGallons = 0; char moreInput = 'y'; while (moreInput == 'y' || moreInput == 'Y') { cout << "Enter miles driven (or 0 to exit): "; cin >> miles; if (miles == 0) break; cout << "Enter gallons used: "; cin >> gallons; double tankfulMPG = miles / gallons; cout << "Miles per gallon for this tankful: " << tankfulMPG << endl; totalMiles += miles; totalGallons += gallons; double totalMPG = totalMiles / totalGallons; cout << "Total miles per gallon for all tankfuls: " << totalMPG << endl; cout << "More entries? (y/n): "; cin >> moreInput; } return 0; } ```

Test, Debug, and Execute the Program

To test the program, you need to execute it in an appropriate environment such as an IDE or command line that supports C++. 1. Run the program and enter miles and gallons for multiple tankfuls: - Example inputs could be: Miles = 100, Gallons = 5; Miles = 200, Gallons = 10. 2. Verify that the calculations for MPG for each tankful and the cumulative MPG are correct. 3. Ensure that the program exits correctly when 'n' is entered or miles are entered as 0. 4. If any errors occur, debug the program by checking user input handling and arithmetic operations.

Key concepts

Pseudocode

Pseudocode is a simplified way of describing the logic and operations of a program without using specific programming language syntax. It helps programmers to conceptualize and design algorithms by outlining the necessary steps in plain language. This can be particularly useful in the planning phase of development. Without worrying about syntax, programmers can focus on logic and structure. Also, it is easier to discuss and refine ideas with others using pseudocode.
In the context of our mileage calculation program, pseudocode serves as a blueprint. It can break down the logic into simple steps like initializing variables and loop operations. For example:

• Initialize total mileage and gallons to zero.
• Use a loop to process each tankful of gasoline until no more entries exist.
• Within the loop, gather user input for miles driven and gallons used.
• Calculate and print the MPG for each tank.
• Update and print the cumulative MPG.

By providing a clear outline through pseudocode, subsequent translation into C++ is more straightforward and less error-prone.

Algorithm Development

Algorithm development is the process of creating a step-by-step procedure to solve a specific problem. It often begins with understanding the problem in detail and figuring out the necessary data to achieve a solution. This is crucial in any programming task, setting the foundation for writing efficient and effective code.
For the mileage calculation, algorithm development involves determining necessary steps:

• Identify input requirements (miles driven and gallons used).
• Break down the logic into simple operations.
• Ensure the process is repeatable for multiple tankfuls.
• Outline how to compute individual and cumulative MPG.

With a well-thought-out algorithm, writing code becomes a translation exercise of transforming logical steps into a programming language like C++. Effective algorithms not only solve the current problem but often anticipate edge cases or unusual user inputs.

Miles Per Gallon Calculation

Calculating the miles per gallon (MPG) is a straightforward arithmetic operation and a common task when assessing vehicular efficiency. It involves dividing the distance covered by an automobile (measured in miles) by the amount of fuel used (measured in gallons).
The formula is: \[\text{MPG} = \frac{\text{miles driven}}{\text{gallons used}}\]Managing individual tankfuls, this simple calculation shows how efficiently a vehicle uses fuel. In our program, we also calculate a cumulative MPG which entails maintaining a running total of mileage and fuel consumption over several trips. The cumulative MPG is calculated in a similar way:\[\text{Cumulative MPG} = \frac{\text{total miles driven}}{\text{total gallons used}}\]This gives drivers a broader view of their vehicle's performance over time, which can be crucial for budgeting fuel expenses and understanding maintenance needs.

While Loop in C++

A while loop in C++ is a control flow statement that allows code to be executed repeatedly, based on a given condition. This is useful in scenarios where the number of iterations is not known in advance, such as reading data until the user decides to stop by entering a sentinel value.
In the context of mileage calculation, a while loop efficiently handles multiple entries for miles and gallons until the user decides there are no more entries. The loop continues as long as the condition checks true, effectively collecting and processing each data entry: ```cpp while (moreInput == 'y' || moreInput == 'Y') { // Perform operations for each tankful } ``` The loop condition checks the user's input, allowing multiple refueling records. Inside the loop, typical operations might include reading values, calculating MPG, and updating totals. It then prompts the user to continue or exit, ensuring the program's shutdown condition is clear and manageable. This structure exemplifies how while loops can manage repetitive tasks efficiently in programming.