Summary  
This chapter demonstrates how to implement function overloading by defining multiple functions with the same name but different parameter types or counts to achieve compile-time polymorphism and cleaner code.  

General domain of usage  
Mathematical computation libraries

#define CATCH_CONFIG_MAIN
#include <catch2/catch.hpp>
#include <cmath>

const double PI = 3.14159;

// Function declarations (to be linked with actual implementation)
double calculateArea(double length, double width);
double calculateArea(double radius);
double calculateArea(double a, double b, double c);

TEST_CASE("Circle area with radius 3 should be ~28.27431", "[calculateArea]") {
    double result = calculateArea(3.0);
    REQUIRE(result == Approx(PI * 3 * 3)); // Area = PI * r^2
}

TEST_CASE("Rectangle area 4 x 6 should be 24", "[calculateArea]") {
    double result = calculateArea(4.0, 6.0);
    REQUIRE(result == Approx(24.0)); // Area = length * width
}

TEST_CASE("Triangle area with sides 5, 4, 6 should be ~9.92157", "[calculateArea]") {
    double result = calculateArea(5.0, 4.0, 6.0);
    double s = (5 + 4 + 6) / 2.0;
    double expected = sqrt(s * (s - 5) * (s - 4) * (s - 6));
    REQUIRE(result == Approx(expected)); // Heron's formula
}

// Additional tests for coverage
TEST_CASE("Circle area with radius 0 should be 0", "[calculateArea]") {
    double result = calculateArea(0.0);
    REQUIRE(result == Approx(0.0)); // Area = 0 for radius 0
}

TEST_CASE("Rectangle area with 0 x 10 should be 0", "[calculateArea]") {
    double result = calculateArea(0.0, 10.0);
    REQUIRE(result == Approx(0.0)); // Area = 0 if any side is 0
}

TEST_CASE("Triangle area with sides 3, 4, 5 should be 6", "[calculateArea]") {
    double result = calculateArea(3.0, 4.0, 5.0);
    REQUIRE(result == Approx(6.0)); // Classic 3-4-5 triangle
}

TEST_CASE("Triangle area with invalid sides should be 0 or NaN", "[calculateArea]") {
    double result = calculateArea(1.0, 2.0, 10.0); // Impossible triangle
    if (!std::isnan(result)) {
        REQUIRE(result == Approx(0.0)); // If not NaN, should be 0
    }
}

test.cpp

Explore the world of C++ functions and delve into their fundamental concepts and practical applications. Gain proficiency in declaring, using, and optimizing functions, including parameter handling, scope management, and function overloading. Learn about recursion, templates, and lambda expression for robust C++ programming. Develop the skills to create modular, efficient, and reusable functions for real-world coding challenges.

Now it's time to dive into the world of C++ functions! Now you will learn some general concepts about functions in C++, including their definition, declaration, and usage. Discover how to declare and call functions, and gain insights into variable scopes, both local and global, for effective program design.

We will delve into specifying and using function arguments in C++ programming. Explore concepts like pass-by-value and pass-by-reference, and understand the role of default arguments; learn how to pass arrays as function arguments and become familiar with constant function arguments.

Now we will learn about how to specify the return value of a function in C++. This includes understanding the data types that functions can return, such as integers, floating-point numbers, and arrays. We will also consider function that have no return value.

Now let's delve into some additional topic in C++! We will explore function overloading, mastering the art of creating multiple functions with the same name but different parameter lists for enhanced code flexibility. Recursion is introduced, teaching the principles of recursive functions, allowing students to solve complex problems efficiently. Additionally, the section covers lambda functions, providing insights into creating concise anonymous functions/

Challenge: Function Overloading Practice

Example

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Challenge: Function Overloading Practice

Example

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