CHAP. 10] BINARY TREES 255
Fig. 10-25
(b) Scan the tree from the left as in Fig. 10-4(b) to obtain
∗+∗ 2 xy↑−∗ 5 ab 3
10.7. Draw all possible nonsimilar: (a) binary treesTwith three nodes; (b) 2-treesT′with four external nodes.
(a) There are five such treesT, which are pictured in Fig. 10-26(a).
(b) Each 2-treeT′with four external nodes is determined by a binary treeTwith three nodes, that is, by a treeTin
part (a). Thus there are five such 2-treesT′which are pictured in Fig. 10-26(b).
Fig. 10-26
BINARY SEARCH TREES, HEAPS
10.8. Consider the binary treeTin Fig.10-22(a).
(a) Why isTa binary search tree?
(b) Suppose ITEM=33 is added to the tree. Find the new treeT.
(a) Tis a binary, search tree since each nodeNis greater than the values in its left subtree and less than the values
in its right subtree.