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  1. #include <iostream>
  2.  
  3. struct Coord{
  4.   int x = 1;
  5.   int y = 1;
  6.   void printCoord(){
  7.     std::cout << "X: " << x << " Y: " << y << std::endl;
  8.   }
  9. };
  10.  
  11. class Base{
  12.  
  13.   public:
  14.   Coord myCoord;
  15.   Base(Coord &coord): myCoord(coord){} // How do I modify this line so Base gets a copy of myCoord?
  16.   virtual void updateCoord(int x, int y){};
  17.  
  18. };
  19.  
  20. class Derived : public Base {
  21.  
  22.   public:
  23.   Derived(Coord &coord): Base(coord){} // Or possibly this line?
  24.   virtual void updateCoord(int x, int y){ 
  25.     myCoord.x = x;
  26.     myCoord.y = y;  
  27.     std::cout << "Updated to:" << std::endl;
  28.     myCoord.printCoord();
  29.   }
  30. };
  31.  
  32. int main(){
  33.   Coord myCoord;
  34.   Base *baseptr;
  35.   Derived d(myCoord);
  36.   baseptr = &d;
  37.  
  38.   std::cout << "Before update:" << std::endl;
  39.   myCoord.printCoord();
  40.   baseptr->updateCoord(2,2);
  41.   std::cout << "After update:" << std::endl;
  42.   myCoord.printCoord();
  43.  
  44.   return 0;
  45. }
Success #stdin #stdout 0.01s 5304KB
comments (?)
stdin 
Standard input is empty
stdout 
Before update:
X: 1 Y: 1
Updated to:
X: 2 Y: 2
After update:
X: 1 Y: 1
https://ideone.com/pC3HdX
language:
C++14 (gcc 8.3)
created:
2 years ago
visibility:
public

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