C++ LANGUAGE RELATIONAL OPERATORS OVERLOADING

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C++ LANGUAGE RELATIONAL OPERATORS OVERLOADING

Relational Operators Overloading 


There are various relational operators supported by C++ 
language like (<, >, <=, >=, ==, etc.) which 
can be used to compare C++ built-in data types. 

You can overload any of these operators, which can be used 
to compare the objects of a class. 

Following example explains how a < operator can be 
overloaded and similar way you can overload other relational operators. 


#include <iostream>
 
using namespace std; 
  
class Distance 
{ 
   private: 
      int feet;             // 0 to infinite 
      int inches;           // 0 to 12 
   public: 
      // required constructors 
      Distance(){ 
         feet = 0; 
         inches = 0; 
      } 
      Distance(int f, int i){ 
         feet = f; 
         inches = i; 
      } 
      // method to display distance 
      void displayDistance() 
      { 
         cout << "F: " << feet << " I:" << inches <<endl; 
      } 
      // overloaded minus (-) operator 
      Distance operator- ()   
      { 
         feet = -feet; 
         inches = -inches; 
         return Distance(feet, inches); 
      } 
      // overloaded < operator 
      bool operator <(const Distance& d) 
      { 
         if(feet < d.feet) 
         { 
            return true; 
         } 
         if(feet == d.feet && inches < d.inches) 
         { 
            return true; 
         } 
         return false; 
      } 
}; 
int main() 
{ 
   Distance D1(11, 10), D2(5, 11); 
  
   if( D1 < D2 ) 
   { 
      cout << "D1 is less than D2 " << endl; 
   } 
   else 
   { 
      cout << "D2 is less than D1 " << endl; 
   } 
   return 0; 
} 
When the above code is compiled and executed, it produces the following result: 
D2 is less than D1