#include <iostream>
#include <assert.h>

struct S
{
	S(int x) : x(x) {}
	
	bool operator==(const S& other) const
	{
		return x == other.x;
	}
	int x;
};

int main() {
	S s1{5};
	S s2{5};
	
	assert(s1 == s2);
	
	assert(!(s1 == 5));
	
	return 0;
}