Answer to Question 33C-1

  //======================================================
  //                isLeaf
  //======================================================
  // isLeaf(T) returns true if T is a leaf.
  //======================================================

  bool isLeaf(ConstTree T)
  {
    return T != NULL && T->left == NULL && T->right == NULL;
  }

  //======================================================
  //                numLeaves
  //======================================================
  // numLeaves(T) returns the number of leaves in tree T.
  //======================================================

  int numLeaves(ConstTree T)
  {
    if(T == NULL)
    {
      return 0;
    }
    else if(isLeaf(T))
    {
      return 1;
    }
    else
    {
      return numLeaves(T->left) + numLeaves(T->right);
    }
  }