#include <cmath>
#include <iostream>

class Node
{
public:
    Node() {}
    virtual ~Node() = default;
    virtual int eval() = 0;
    
private:
};

class Number : public Node
{
public:
    Number(int value) : value{value} {}

    int eval() override
    {
	return value;
    }
private:
    int value;
};

class Binary : public Node
{
public:
    Binary(Node& lhs, Node& rhs) : lhs{lhs}, rhs{rhs} {}
protected:
    Node& lhs;
    Node& rhs;
};

class Addition : public Binary
{
public:
    Addition(Node& lhs, Node& rhs) : Binary(lhs, rhs) {}

    int eval() override
    {
	return lhs.eval() + rhs.eval();
    }
private:
};

class Multiplication : public Binary
{
public:
    Multiplication(Node& lhs, Node& rhs) : Binary(lhs, rhs) {}

    int eval() override
    {
	return lhs.eval() * rhs.eval();
    }
private:
};

int main()
{
    Number five{5};
    Number three{3};
    Number two{2};
    Multiplication multiplication{five, two};
    Addition addition{three, multiplication};
    std::cout << addition.eval() << std::endl;
}