//Huffman tree node abstract base class

template <typename E> class HuffNode

{

public:

virtual ~HuffNode() {}

virtual int weight() =0;

virtual bool isLeaf() =0;

};

template <typename E>

class LeafNode : public HuffNode<E>

{

private:

E it;

int wgt;

public:

LeafNode(const E& val, int freq)

{

it = val;

wgt = freq;

}

int weight() {return wgt;}

E val() {return it;}

bool isLeaf() {return true;}

};

template<typename E>

class IntlNode : public HuffNode<E>

{

private:

HuffNode<E>* lc;

HuffNode<E>* rc;

int wgt;

public:

IntlNode(HuffNode<E>* l, HuffNode<E>* r)

{

wgt = l->weight() + r->weight();

lc = l;

rc = r;

}

int weight() {return wgt;}

bool isLeaf() {return false;}

HuffNode<E>* left() const {return lc;}

void setLeft(HuffNode<E>* b)

{

lc = (HuffNode<E>*)b;

}

HuffNode<E>* right() const {return rc;}

void setRight(HuffNode<E>* b)

{

rc = (HuffNode<E>*)b;

}

};