Exam 17: Tree Structures

Given the Node class discussed in section 17.1 (partially shown below), select an expression to complete the isLeaf method, which is designed to return true if the node is a leaf, false otherwise. class Node { Public Object data; Public List<Node> children; ) . . Public boolean isLeaf() { Return _______________; } }

What is the complexity of removing an element from a heap?

If the postorder traversal of an expression tree is 8, 2, +, 5, /, what is the numeric result of that Reverse Polish Notation expression?

Consider the following binary search tree: Which of the following sequences correctly represents postorder traversal of this tree?

Consider the following tree diagram: Which of the following nodes are child nodes?

Consider a balanced binary tree with 520 nodes. The average length of all paths from the root to the leaves is approximately ____.

Consider the following tree diagram: Which of the following nodes are siblings?

If a min-heap has 14 nodes, what is known for certain when we add a new node? I every level of the tree will be fully occupied II the tree does not grow a new level III the root contains the smallest element

Consider the following binary search tree: Which of the following sequences correctly represents preorder traversal of this tree?

Consider the following tree diagram: Which of the following nodes are parent nodes?

If both of the child references of a binary tree node are non-null, it follows that the node must be ____.

The nodes in our binary search tree implement the Comparable interface. Which tree operations benefit from this design decision? I add II search III delete

The height of a tree can be obtained by recursively computing the heights of its subtrees, while keeping track of the height of the deepest subtree. Given the Node class discussed in section 17.1 (partially shown below), select an expression to complete the recursive method height, which is designed to return the height of the tree rooted at a node. class Node { Public Object data; Public List<Node> children; ) . . Public int height() { Int maxChildHeight = 0; For (Node child : children) { Int childHeight = child.height(); If (childHeight > maxChildHeight) MaxChildHeight = childHeight; } Return _________________; } }

Consider the following Huffman encoding tree: The letter H will be encoded as ____.

If the child references of a binary tree node are both null, the node is ____.

Consider the following tree diagram: Which arithmetic expression is represented by this tree?

A binary tree with 260 nodes has a height of approximately ____.

Given the BinarySearchTree class discussed in section 17.3 (partially shown below), select a sequence of statements to complete the recursive postorder method. The method performs a postorder traversal of the binary search tree rooted at node n. public class BinarySearchTree { Private Node root; Public BinarySearchTree() {...} Public void postorderTraversal() { Postorder(root); } Private static void postorder(Node n) { If (n != null) { ____________________ ____________________ ____________________ } } ) . . }

Consider the following tree diagram: Which of the following statements is NOT correct?

Given the BinaryTree class discussed in section 17.2 (partially shown below), select an expression to complete the static recursive helper method countLeaves, which returns the number of leaf nodes in the binary tree rooted at node n. public class BinaryTree { Private Node root; Public BinaryTree() { Root = null; } Public BinaryTree(Object rootData, BinaryTree left, BinaryTree right) { Root = new Node(); Root.data = rootData; Root.left = left.root; Root.right = right.root; } Class Node { Public Object data; Public Node left; Public Node right; } Public int countLeaves() { Return countLeaves(root); } Public static int countLeaves (Node n) { If (n == null) { Return 0; } Else if (_____________________) { Return 1; } Else { Return countLeaves(n.left) + countLeaves(n.right); } } }