Project 3 - Statements, Expressions, and Loops

A power station is on one side of a river that is one-half mile wide, and a factory is eight miles downstream on the other side of the river. It costs $7 per foot to run power lines over land and $9 per foot to run them under water. Your objective is to determine the most economical path to lay the power line. That is, determine how long the power line should run under water and how long it should run over land to achieve the minimum total cost of laying the power line.

In general we want to solve this problem for given width of the river, distance to the factory, and cost of running power lines over land and water. Writing a program to solve this optimization problem allows us to use it in any possible scenario without having to recompute each time by hand 😃.

Objectives

• Creating code that is easier to read and modify/maintain.
  • Creating and using user defined functions.
  • Using constants.
• Formatting output to a standard.
• Use the Pythagorean theorem
• Use loops, branches and expressions

Task 1 - Generate Build Files

There are two scripts in the root directory named clean.sh and release.sh. One creates a release build to compile your project and the other will delete all the temporary files that are created during the build process.

Run the release.sh script from the terminal to setup your project. Note that your output will be slightly different than what is shown below because cmake configures the build system specific to the system that it is running on.

shane|(master *%=):solution$ ./release.sh
-- The CXX compiler identification is AppleClang 14.0.3.14030022
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Check for working CXX compiler: /Library/Developer/CommandLineTools/usr/bin/c++ - skipped
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- Configuring done
-- Generating done
-- Build files have been written to: ...

Task 2 - Write the program

Write a program that prompts the user to enter:

• The distance of the factory downstream on the other side of the river.
• The width of the river.
• The cost of laying the power line over land.
• The cost of laying the power line under water.

The program then determines and outputs the length of the power line that should run under water and the length that should run over land so that the cost of constructing the power line is at the minimum. The program should also output the total cost of constructing the power line. You can make the following assumptions:

1. Move down the river in ¼ mile (1320’) increments when determining the cost of laying the cable.
2. The power station and the factory are right next to the river.
3. You can disregard the z axis (the depth of the cable) when determining the cost.

Your code should:

• Create user defined functions whenever warranted/possible (remember, if you do the identical set of calculations multiple times then you should use functions). This project DOES necessitate functions. Create the following functions (at a minimum):
  • computeDiag(double base, double height) - computes the ‘water’ distance ,the diagonal of the triangle
  • computeWaterCost(double length, double cost) - computes the water cost
  • computeLandCost(double length, double cost) - computes the land cost
• Use ‘constants’ when warranted.
• Cable length should be displayed in miles to 4 decimal places.
• Dollar amounts should be preceded by a dollar sign (‘$’) to 2 decimal places.

Your output shall:

• List the cable length going over land and its cost with an appropriately written prompt that identifies what the length and cost represents.
• List the cable length going across the river and its cost with an appropriately written prompt that identifies what the length and cost represents.
• List the overall cost to lay the cable with an appropriately written prompt that identifies what the cost represents.
• The execution of your program should display the output below (text stated should be exact):

Enter the distance downstream to the factory in miles: 8
Enter the width of the river in miles: .5
Enter the dollar cost per foot to run power over land: 7
Enter the dollar cost per foot to run power under water: 9
Checking distance over water when land distance is 0.00 miles...380901.78
Checking distance over water when land distance is 0.25 miles...378285.66
Checking distance over water when land distance is 0.50 miles...375671.12
Checking distance over water when land distance is 0.75 miles...373058.34
Checking distance over water when land distance is 1.00 miles...370447.49
Checking distance over water when land distance is 1.25 miles...367838.80
Checking distance over water when land distance is 1.50 miles...365232.50
Checking distance over water when land distance is 1.75 miles...362628.88
Checking distance over water when land distance is 2.00 miles...360028.29
Checking distance over water when land distance is 2.25 miles...357431.10
Checking distance over water when land distance is 2.50 miles...354837.78
Checking distance over water when land distance is 2.75 miles...352248.87
Checking distance over water when land distance is 3.00 miles...349665.04
Checking distance over water when land distance is 3.25 miles...347087.08
Checking distance over water when land distance is 3.50 miles...344515.95
Checking distance over water when land distance is 3.75 miles...341952.84
Checking distance over water when land distance is 4.00 miles...339399.24
Checking distance over water when land distance is 4.25 miles...336857.02
Checking distance over water when land distance is 4.50 miles...334328.57
Checking distance over water when land distance is 4.75 miles...331817.00
Checking distance over water when land distance is 5.00 miles...329326.44
Checking distance over water when land distance is 5.25 miles...326862.44
Checking distance over water when land distance is 5.50 miles...324432.70
Checking distance over water when land distance is 5.75 miles...322048.19
Checking distance over water when land distance is 6.00 miles...319724.99
Checking distance over water when land distance is 6.25 miles...317487.71
Checking distance over water when land distance is 6.50 miles...315375.72
Checking distance over water when land distance is 6.75 miles...313455.76
Checking distance over water when land distance is 7.00 miles...311848.98
Checking distance over water when land distance is 7.25 miles...310793.95
Checking distance over water when land distance is 7.50 miles...310801.71
Checking distance over water when land distance is 7.75 miles...313004.49


The most cost effective solution is:

Lay power line across land for 7.2500 miles at a cost of $267960.00
Lay power line under water for 0.9014 miles at a cost of $42833.95
The total cost = $310793.95.

Task 3 - Testing

Your instructor will provide you with testing scripts that were demonstrated in class to help guide your development. These will be posted in canvas along with instructions on how to use them in your project.

Task 4 - Complete the Retrospective

Once you have completed all the tasks open the file Retrospective.md and complete each section that has a TODO label. Reference the grading rubric for details on how this will be graded.

Task 5 - Add, Commit, Push your code

Once you are finished you need to make sure that you have pushed all your code to GitHub for grading! You will not be submitting anything to canvas everything will be submitted through GitHub as demonstrated in class.