Since binomial trees are simply general trees with a special shape, we can make use of the GeneralTree class presented in Section to implement the BinomialTree class. (See Figure ).
Program introduces the BinomialQueue class and the inner class BinomialTree. The BinomialTree class extends the GeneralTree class introduced in Program .
No new fields a declared in the BinomialTree class. Remember that the implementation of the GeneralTree class uses a linked list to contain the pointers to the subtrees, since the degree of a node in a general tree may be arbitrarily large. Also, the GeneralTree class already keeps track of the degree of a node in its degree field. Since the degree of the root node of a binomial tree of order k is k, it is not necessary to keep track of the order explicitly. The degree variable serves this purpose nicely.