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  1. #include <iostream>
  2. #include <vector>
  3. using namespace std;
  4.  
  5. class Base;
  6. class Derived;
  7. struct Visitor {
  8. 	void visit(Base *b) {cout << "BASE" << endl;}
  9. 	void visit(Derived *d) {cout << "DERIVED" << endl; }
  10. };
  11. class Base {
  12. private:
  13. 	vector<Base*> nodes;
  14. public:
  15. 	Base(){};
  16. 	Base(initializer_list<Base*> i) : nodes(i){}
  17. protected:
  18. 	virtual void accept(Visitor *v) {
  19. 		v->visit(this);
  20. 	}
  21. public:
  22. 	void iterate(Visitor *v) {
  23. 		this->accept(v);
  24. 		for (auto n : nodes) {
  25. 			n->iterate(v);
  26. 		}
  27. 	}
  28. };
  29. class Derived : public Base {
  30. public:
  31. 	Derived(initializer_list<Base*>i):Base(i){}
  32. 	Derived(){}
  33. protected:
  34. 	virtual void accept(Visitor *v) override {
  35. 		v->visit(this);
  36. 	}
  37. };
  38.  
  39. int main() {
  40. 	Base bb{new Base, new Base{new Derived{new Derived,new Base}}, new Derived{new Derived,new Base}};
  41. 	bb.iterate(new Visitor);
  42. 	return 0;
  43. }
Success #stdin #stdout 0s 4316KB
comments (?)
stdin
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Standard input is empty
stdout
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BASE
BASE
BASE
DERIVED
DERIVED
BASE
DERIVED
DERIVED
BASE
https://ideone.com/u9tEzy
language:
C++ (gcc 8.3)
created:
6 years ago
visibility:
public

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