#include <iostream>
#include <typeinfo>
using namespace std;
 
template <class T1, class T2>
auto iloczyn (T1 a, T2 b) -> decltype(a*b) {
	cout<<"we've got: "<<typeid(decltype(a)).name()<<" and "<<typeid(decltype(b)).name()<<endl;
	return a*b;
}
 
class test {
public:
	double val;
	test (double val = 0) : val(val) {}
	friend test operator * (test a, test b) {
		return test(a.val * b.val);
	}
 
	friend ostream & operator << (ostream &out, test a) {
		return out<<a.val;
	}
};
 
int main() {
	cout<<iloczyn(2.4, test(2))<<endl;
}
 

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