#include <iostream>
#include <unordered_map>
using namespace std;

struct Key {
    double x;
    double y; 
    double z;

    bool operator==(const Key& k) const{
      return (x == k.x && y == k.y && z == k.z);
    }
};

namespace std {
	template <> struct hash<Key> {
		unsigned operator()(const Key& arg) const {
			return 0;
		}		
	};
}

int main() {
	std::unordered_map<Key, int> map = {{{1.01, 2.02, 3.03}, 333}};
	return 0;
}