#include <Core/Core.h>

using namespace Upp;

struct Oper {
	virtual double Execute() = 0;
	virtual ~Oper() {}
};

struct BinOper : Oper {
	One<Oper> a;
	One<Oper> b;
};

struct Add : BinOper {
	virtual double Execute() { return a->Execute() + b->Execute(); }
};

struct Sub : BinOper {
	virtual double Execute() { return a->Execute() - b->Execute(); }
};

struct Mul : BinOper {
	virtual double Execute() { return a->Execute() * b->Execute(); }
};

struct Div : BinOper {

		
		
		
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