#include <iostream>
#include <map>
#include <cstring>

template <typename T, typename D>
class Biection <T, D>{
public:
    D getPairX(T x);
    T getPairY(D y);
    void add(T x, D y);
private:
    std::map <T, D> _map;
};



template <typename T, typename D>
D Biection::getPairX(T x) {
    std::map::iterator it = _map.find(x);
    if(it != _map.end())
        return it->second;
    else{
        std::string str = "Element not found!";
        throw str;
    }
}

template <typename T, typename D>
T Biection::getPairY(D y) {
    for(std::map::iterator it = _map.begin(); it != _map.end(); ++it){
        if(it->second == y)
            return it->first;
    }
    std::string str = "Element not found!";
    throw str;
}

template <typename T, typename D>
void Biection::add(T x, D y) {
    try {
        getPairX(x);
    }catch (std::string e){
        try{
            getPairY(y);
        }catch (std::string e){
            _map.insert(std::pair(x, y));
            return;
        }
    }
    std::string str = "This biection already exists!";
    throw str;
}

int main() {

    return 0;
}