i have this code here that i have written out and im i want to convert it using functions.

basically it is a geometry calculator that will let you calculate the area for any geometric object (ie rectangle, cirlce, triangle)

basically i have to rewrite the code and add a loop so that the uuser can calculate more than one geometric object.

here was my code that was only with switch statements:

```
#include <iostream>
#include <iomanip>
#include <cmath>
using namespace std;
int main ()
{
//Declaration of Variables.
double circleArea, rectangleArea, triangleArea,
length, width, height, base, radius;
char choice;
const double PI = 3.14159;
//Display the menu.
cout << "\tGeometry Calculator" << endl << endl;
cout << setw(10) << "1. Calculate the Area of a [C]ircle" << endl;
cout << setw(10) << "2. Calculate the Area of a [R]ectangle" << endl;
cout << setw(10) << "3. Calculate the Area of a [T]riangle" << endl;
cout << setw(6) << "4. [Q]uit" << endl;
cout << endl;
//Prompt User for choice.
cout << setw(10) << "Enter your choice (1-4)" << endl;
cin >> choice;
cout << endl;
//Calculate the area of a Circle.
switch (choice)
{
case 'C':
case 'c':
case '1':
cout << "Enter the radius of the circle: ";
cin >> radius;
if (radius < 0)
{
cout << "Number must be greater than 0. Try again" << endl;
}
else
{
circleArea = PI * pow(radius, 2);
cout << "The area of the circle is: " << circleArea;
}
cout << endl;
break;
//Calculate the area of a Rectangle.
case 'R':
case 'r':
case '2':
cout << "Enter the length and width of the rectangle: ";
cin >> length >> width;
if (length < 0 || width < 0)
{
cout << "Number must be greater than 0. Try again" << endl;
}
else
{
rectangleArea = length * width;
cout << "The area of the rectangle is: " << rectangleArea;
}
cout << endl;
break;
//Calculate the area of a Triangle.
case 'T':
case 't':
case '3':
cout << "Enter the base and height of the triangle: ";
cin >> base >> height;
if (base < 0 || height < 0)
{
cout << "Number must be greater than 0. Try again" << endl;
}
else
{
triangleArea = base * height * .5;
cout << "The area of the triangle is: " << triangleArea;
}
cout << endl;
break;
//Quit the program.
case 'Q':
case 'q':
case '4':
cout << "End of Program" << endl;
cout << "Have a Great Day!" << endl;
cout << endl;
break;
//Invalid number.
default:
cout << "That is an invalid choice." << endl;
cout << "Please select choices 1-4." << endl;
break;
}
return 0;
}
```

im thinking that the layout should be like this:

function prototypes

int main()

loop (on yes)

function calls

-->switch statement

loop (on no)

---> end program

///functions below

it seems that this is something that is very easy--but the switch statment throws me off as im not sure if it should be part of the function or in main itself.

thanks for the help!!