Question

(Функції с++) Визначити функцію CircleS(R) дійсного типу, що знаходить площу круга радіуса R (R — дійсне). За допомогою цієї функції знайти площі трьох кругів з вказаними користувачем радіусами. Площу круга радіуса R рахувати за формулою S= π·R 2 . В якості значення π використовувати 3.14.

Answer 1

#include <iostream>

using namespace std;

float CircleS (float r)

{

   return 2 * 3.14 * r;

}

int main()

{

   cout << CircleS(5) << endl;

   cout << CircleS(1) << endl;

   cout << CircleS(10) << endl;

   return 0;

}

Answer 2

Function to Calculate the Area of a Circle

To define a function in C++ that calculates the area of a circle, you can follow these steps:

1. Declare the function with the appropriate return type and parameter(s). 2. Implement the function body, which performs the necessary calculations. 3. Return the calculated area.

Here's an example of how you can define the `CircleS` function in C++ to calculate the area of a circle:

#include

double CircleS(double R) {
    const double pi = 3.14;
    double area = pi * R * R;
    return area;
}

int main() {
    double radius1, radius2, radius3;
    // Get the radius values from the user
    std::cout << "Enter the radius of the first circle: ";
    std::cin >> radius1;
    std::cout << "Enter the radius of the second circle: ";
    std::cin >> radius2;
    std::cout << "Enter the radius of the third circle: ";
    std::cin >> radius3;

// Calculate the areas using the CircleS function
    double area1 = CircleS(radius1);
    double area2 = CircleS(radius2);
    double area3 = CircleS(radius3);

// Display the results
    std::cout << "The area of the first circle is: " << area1 << std::endl;
    std::cout << "The area of the second circle is: " << area2 << std::endl;
    std::cout << "The area of the third circle is: " << area3 << std::endl;

return 0;
}

In this example, the `CircleS` function takes a single parameter `R`, which represents the radius of the circle. It calculates the area of the circle using the formula `S = π * R^2`, where `π` is approximated as 3.14. The calculated area is then returned by the function.

In the `main` function, three radius values are obtained from the user using `std::cin`. The `CircleS` function is called with each radius value to calculate the corresponding areas. Finally, the results are displayed using `std::cout`.

Please note that the value of `π` is approximated as 3.14 in this example. For more accurate results, you can use the `M_PI` constant from the `` library, which provides a more precise value of `π`.