Object-Oriented Programming in C++

// PL5/aclass.cpp
// A populated class for 3 vectors
// Niels Walet, last updated 09/02/2020
#include<iostream>
class vector3
{
private:
  double x{};
  double y{};
  double z{}; 
public:
  // Constructors and destructor
  vector3() = default ;
  vector3(double x_in, double y_in, double z_in) : x{x_in}, y{y_in}, z{z_in} {} 
  ~vector3(){std::cout<<"Destroying vector"<<std::endl;} 
  // Access functions to set and get vector components
  void set_x(const double x_in) {x=x_in;} 
  void set_y(const double y_in) {y=y_in;}
  void set_z(const double z_in) {z=z_in;}
  double get_x() const {return x;}
  double get_y() const {return y;}
  double get_z() const {return z;}
  // Function to print out vector
  void show() const {std::cout<<"("<<x<<","<<y<<","<<z<<")"<<std::endl;}
  // Function to add a scalar to each vector component
  void add_scalar(const double s) {x+=s; y+=s; z+=s;}
};