Binary trees

Question 1

What is the first node added to a binary tree called?
a) Leaf node
b) Root node
c) Parent node
d) Child node

Answer 1

b) Root node

Question 2

How many child nodes can a single node in a binary tree have?
a) One
b) Two
c) Three
d) Unlimited

Answer 2

b) Two

Question 3

What happens when a new node’s value is less than the current node’s value during insertion?
a) It is added to the left of the current node
b) It is added to the right of the current node
c) It is ignored
d) The tree is rebalanced

Answer 3

a) It is added to the left of the current node

Question 4

What is the name of the class property in the Node class that refers to the left child?
a) leftChild
b) leftNode
c) leftLink
d) childLeft

Answer 4

b) leftNode

Question 5

What does the insert() method in the Node class do when encountering a null left or right node?
a) Replaces it with a new node
b) Deletes the current node
c) Ignores the insertion
d) Moves to the parent node

Answer 5

a) Replaces it with a new node

Question 6

What type of class is the Node class described as, due to its references to itself?
a) Recursive class
b) Cyclic class
c) Self-referential class
d) Linked class

Answer 6

c) Self-referential class

Question 7

What property does the Tree class use to store the first node of the tree?
a) root
b) firstNode
c) startNode
d) initialNode

Answer 7

a) root

Question 8

What happens when the insert() method in the Tree class is called and the root is null?
a) An error occurs
b) A new Node object is assigned to the root
c) The method exits without action
d) The tree is cleared

Answer 8

b) A new Node object is assigned to the root

Question 9

In the traversal process, what is the first step taken when the current node is null?
a) Print a null value
b) Return from the method
c) Insert a default node
d) Move to the next sibling

Answer 9

b) Return from the method

Question 10

What is the output of a left-favored traversal of the tree created in the example with values [47, 48, 20, 15, 26, 18]?
a) 15, 18, 20, 26, 47, 48
b) 48, 47, 26, 20, 18, 15
c) 47, 20, 15, 18, 26, 48
d) 26, 15, 20, 18, 48, 47

Answer 10

a) 15, 18, 20, 26, 47, 48

Question 11

Which method is used to print the tree in descending order?
a) traverse()
b) reverse()
c) traverseFromRoot()
d) reverseFromRoot()

Answer 11

d) reverseFromRoot()

Question 12

What feature of a binary tree allows it to efficiently store and retrieve ordered data?
a) Self-balancing nodes
b) Branch sorting during insertion
c) Hierarchical memory allocation
d) Contiguous storage

Answer 12

b) Branch sorting during insertion

Question 13

In a binary tree, what happens if you attempt to insert a value equal to an existing node?
a) The value is ignored
b) The tree duplicates the node
c) The value replaces the existing one
d) The tree rebalances itself

Answer 13

a) The value is ignored

Question 14

What modification allows a binary tree to return values in descending order during traversal?
a) Adding an extra property to each node
b) Traversing right nodes before left nodes
c) Reversing the root and leaf nodes
d) Adding duplicate nodes

Answer 14

b) Traversing right nodes before left nodes

Question 15

Which of the following is NOT a common application of binary trees?
a) File systems
b) Email storage
c) Network routing
d) Backtracking algorithms

Answer 15

d) Backtracking algorithms