Analysis of overloading usage of C++ functions

Function overloading allows the creation of functions with different parameter lists using the same name, allowing for code flexibility. Rules include: the function name is the same, the parameter list is different, and may be of different type or number. For example, a class that calculates area contains overloaded functions for different shapes, and the corresponding function can be called to calculate the area based on the shape type.

Analysis of overloading usage of C functions

What is function overloading?

Function overloading allows the creation of multiple functions with different parameter lists using the same name. This makes the code more flexible and reusable.

The syntax of overloaded functions

returnType functionName(parameterList1);
returnType functionName(parameterList2);
...
returnType functionName(parameterListN);

Where:

• returnType is the return type of the function.
• functionName is the name of the function.
• parameterList is the parameter list of the function.

Rules for overloading functions

• The functions have the same name.
• The parameter list is different.
• The parameter types or numbers in the parameter list are different.

Practical case

Suppose we have a class that calculates area, with specialized functions for different shapes:

class Shape {
public:
  virtual double area() const = 0;
};

class Rectangle : public Shape {
public:
  Rectangle(double width, double height): width(width), height(height) {}
  double area() const override {
    return width * height;
  }
private:
  double width, height;
};

class Circle : public Shape {
public:
  Circle(double radius): radius(radius) {}
  double area() const override {
    return M_PI * radius * radius;
  }
private:
  double radius;
};

To calculate an For the area of ​​a shape, we can call the corresponding overloaded function according to its type:

int main() {
  Shape* shapes[] = { new Rectangle(2.0, 3.0), new Circle(1.0) };
  for (int i = 0; i < 2; i++) {
    std::cout << "Area of shape " << i << ": " << shapes[i]->area() << std::endl;
  }
  return 0;
}

Output:

Area of shape 0: 6
Area of shape 1: 3.14159

Note:

• Heavy The order in which functions are loaded does not affect the results of function calls.
• Overloaded functions can have different access control levels (such as public, private).
• Overloaded functions can have different default parameter values.

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