#include <iostream>
#include <vector>
 
struct Entity
{
	virtual ~Entity() = default;
	virtual void Update() { std::cout << "Entity\n"; }
};
 
struct NPC : Entity
{
	virtual void Update() { std::cout << "NPC\n"; }
};
 
struct Trap : NPC
{
	virtual void Update() { std::cout << "Trap\n"; }
};
 
 
int main() {
	Entity the_entity;
	NPC npc;
	Trap trap;
	std::vector<Entity*> entities = {&the_entity, &npc, &trap};
 
	for (auto* entity : entities)
	{
		entity->Update();
	}
}
 

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