075-C++

C++ 关系运算符重载

#include <iostream>using namespace std; class Distance{   private:      int feet;             // 0 到无穷      int inches;           // 0 到 12   public:      // 所需的构造函数      Distance(){         feet = 0;         inches = 0;      }      Distance(int f, int i){         feet = f;         inches = i;      }      // 显示距离的方法      void displayDistance()      {         cout << "F: " << feet << " I:" << inches <<endl;      }      // 重载负运算符（ - ）      Distance operator- ()        {         feet = -feet;         inches = -inches;         return Distance(feet, inches);      }      // 重载小于运算符（ < ）      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;}