C++ examples for Class:Operator Overload
Implementing the * operator for the Pool class to pre-multiply by an integer
#include <iostream> #include <iostream> #include <iomanip> class Pool//from w ww . j a v a 2 s. c om { private: double length {1.0}; double width {1.0}; double height {1.0}; public: // Constructors Pool(double lv, double wv, double hv) : length {lv}, width {wv}, height {hv} {} Pool() {} // No-arg constructor Pool(const Pool& pool) // Copy constructor : length {pool.length}, width {pool.width}, height {pool.height} {} double volume() const // Function to calculate the volume { return length*width*height; } // Accessors double getLength() const { return length; } double getWidth() const { return width; } double getHeight() const { return height; } bool operator<(const Pool& aPool) const; // Less-than operator bool operator<(double aValue) const; // Compare Pool volume < double value Pool operator+(const Pool& aPool) const; // Function to add two Pool objects Pool operator*(int n) const; // Post-multiply an object by an integer friend std::ostream& operator<<(std::ostream& stream, const Pool& pool); }; // Pre-multiply an object by an integer inline Pool operator*(int n, Pool& pool) { return Pool {pool.getLength(), pool.getWidth(), n*pool.getHeight()}; } // Post-multiply an object by an integer inline Pool Pool::operator*(int n) const { return Pool {length, width, n*height}; } // Less-than comparison for Pool objects inline bool Pool::operator<(const Pool& aPool) const { return volume() < aPool.volume(); } // Compare the volume of a Pool object with a constant inline bool Pool::operator<(double aValue) const { return volume() < aValue; } // Function comparing a constant with volume of a Pool object inline bool operator<(double aValue, const Pool& aPool) { return aValue < aPool.volume(); } // Operator function to add two Pool objects inline Pool Pool::operator+(const Pool& aPool) const { // New object has larger length and width, and sum of heights return Pool {length > aPool.length ? length : aPool.length, width > aPool.width ? width : aPool.width, height + aPool.height}; } inline std::ostream& operator<<(std::ostream& stream, const Pool& pool){ stream << " Pool(" << std::setw(2) << pool.length << "," << std::setw(2) << pool.width << "," << std::setw(2) << pool.height << ")"; return stream; } int main() { Pool pool {2, 3, 4}; std::cout << "Pool is " << pool << std::endl; int n {3}; Pool newPool = n*pool; std::cout << "After pre-multiplying by " << n << " pool is " << newPool << std::endl; }