template <class Predicate> 
class binary_negate 
    : public binary_function<Predicate::first_argument_type,
                 Predicate::second_argument_type, bool> {
protected:
    Predicate pred;
public:
    binary_negate(const Predicate& x) : pred(x) {}
    bool operator()(const first_argument_type& x, 
            const second_argument_type& y) const {
    return !pred(x, y); 
    }
};