template\c{\fbox{test version}
class sortedtree : public tree{ public: sortedtree( tree * p, T& n ):tree (p,n){} protected: bool invariant() {return sorted()&&tree ::invariant();} int sorted(); check for order
};
template\c{\fbox{test version}
class sortedtree : public tree{ public: sortedtree( tree * p, T& n ):tree (p,n){} protected: bool invariant() {return sorted()&&tree ::invariant();} int sorted(); check for order
};