Question 1

Which of the following is NOT an operation supported by a stack interface?

Accepted Answer

A)  push 
B)  insert 
C)  clear 
D)  peek 
A)  push 
B)  insert 
C)  clear 
D)  peek

Question 2

In the algorithm to evaluate a postfix expression, what does the algorithm do when an operator is encountered?

Accepted Answer

A)  pop the resulting value from the stack 
B)  push the preceding operands onto the stack 
C)  apply the operator to the two preceding operands 
D)  push the operator onto the stack 
A)  pop the resulting value from the stack 
B)  push the preceding operands onto the stack 
C)  apply the operator to the two preceding operands 
D)  push the operator onto the stack

Question 3

In the algorithm to evaluate a postfix expression, what does the algorithm do when an operand is encountered?

Accepted Answer

A)  pop the operand from the stack 
B)  push the operand onto the stack 
C)  pop the operator from the stack 
D)  push an operator onto the stack 
A)  pop the operand from the stack 
B)  push the operand onto the stack 
C)  pop the operator from the stack 
D)  push an operator onto the stack

Question 4

When using a stack to evaluate the balance of brackets and parentheses in an expression, what is the final step?

Accepted Answer

A)  at the end of the expression, if a final closing bracket is found, the brackets balance 
B)  at the end of the expression, if the stack is empty, the brackets do not balance 
C)  at the end of the expression, if the stack is full, the brackets balance 
D)  at the end of the expression, if the stack is empty, the brackets balance 
A)  at the end of the expression, if a final closing bracket is found, the brackets balance 
B)  at the end of the expression, if the stack is empty, the brackets do not balance 
C)  at the end of the expression, if the stack is full, the brackets balance 
D)  at the end of the expression, if the stack is empty, the brackets balance

Question 5

The first step in evaluating a postfix expression is to scan the expression from left to right.

Accepted Answer

A) True 
 B)False

Question 6

In the algorithm that checks for a balanced expression, which of the following is true if a closing bracket is encountered?

Accepted Answer

A)  if the stack is empty, the brackets balance 
B)  if the item on the top of the stack is a closing bracket of the same type, the brackets balance 
C)  if the stack is empty or the item on the top of the stack is not an opening bracket of the same type, the brackets don't balance 
D)  if the stack is empty or the item on the bottom of the stack is an opening bracket of the same type, the brackets balance 
A)  if the stack is empty, the brackets balance 
B)  if the item on the top of the stack is a closing bracket of the same type, the brackets balance 
C)  if the stack is empty or the item on the top of the stack is not an opening bracket of the same type, the brackets don't balance 
D)  if the stack is empty or the item on the bottom of the stack is an opening bracket of the same type, the brackets balance

Question 7

Using a stack is a good approach to determining if the use of brackets in an expression is balanced.

Accepted Answer

A) True 
 B)False

Question 8

Addition and subtraction have higher precedence when evaluating an infix expression.

Accepted Answer

A) True 
 B)False

Question 9

The time complexity of the postfix expression evaluation algorithm is O( n2 ) .

Accepted Answer

The time complexity of the postfix expre

Question 10

Which of the following is NOT an application of stacks in computer science?

Accepted Answer

A)  implementation of a hash-based database search function 
B)  managing computer memory in support of function calls 
C)  supporting the undo feature in a text editor 
D)  maintaining a history of visited links by a web browser 
A)  implementation of a hash-based database search function 
B)  managing computer memory in support of function calls 
C)  supporting the undo feature in a text editor 
D)  maintaining a history of visited links by a web browser

Question 11

What is the function of the peek method in a stack implementation?

Accepted Answer

A)  to return the bottom item without removing it 
B)  to return the top item without removing it 
C)  to return the top item and remove it from the stack 
D)  to return the bottom item and remove it from the stack 
A)  to return the bottom item without removing it 
B)  to return the top item without removing it 
C)  to return the top item and remove it from the stack 
D)  to return the bottom item and remove it from the stack

Question 12

To avoid stack overflow, the stack algorithm should raise an error if an item is added to a full stack.

Accepted Answer

A) True 
 B)False

Question 13

When evaluating an arithmetic expression, first you transform it from its postfix form to its infix form.

Accepted Answer

A) True 
 B)False

Question 14

When converting from infix form to postfix form, parentheses are added to the equation.

Accepted Answer

A) True 
 B)False

Question 15

What is the operation that adds items to a stack?

Accepted Answer

A)  get 
B)  set 
C)  push 
D)  pop 
A)  get 
B)  set 
C)  push 
D)  pop

Question 16

The Node class for use in the linked structure stack contains three fields: data, next, and previous.

Accepted Answer

A) True 
 B)False

Question 17

The operation for removing an item from the stack is called push.

Accepted Answer

A) True 
 B)False

Question 18

Stack interfaces implement a peek operation for examining the element at the top of the stack.

Accepted Answer

A) True 
 B)False

Question 19

A Python list structure and its methods implement a stack perfectly.

Accepted Answer

A) True 
 B)False

Question 20

In a linked structure stack implementation, efficient pushing and popping require adding and removing of nodes at the head of the linked sequence.

Accepted Answer

A) True 
 B)False

Which of the following is NOT an operation supported by a stack interface?

In the algorithm to evaluate a postfix expression, what does the algorithm do when an operator is encountered?

In the algorithm to evaluate a postfix expression, what does the algorithm do when an operand is encountered?

When using a stack to evaluate the balance of brackets and parentheses in an expression, what is the final step?

The first step in evaluating a postfix expression is to scan the expression from left to right.

In the algorithm that checks for a balanced expression, which of the following is true if a closing bracket is encountered?

Using a stack is a good approach to determining if the use of brackets in an expression is balanced.

Addition and subtraction have higher precedence when evaluating an infix expression.

The time complexity of the postfix expression evaluation algorithm is O( n² ) .

Which of the following is NOT an application of stacks in computer science?

What is the function of the peek method in a stack implementation?

To avoid stack overflow, the stack algorithm should raise an error if an item is added to a full stack.

When evaluating an arithmetic expression, first you transform it from its postfix form to its infix form.

When converting from infix form to postfix form, parentheses are added to the equation.

What is the operation that adds items to a stack?

The Node class for use in the linked structure stack contains three fields: data, next, and previous.

The operation for removing an item from the stack is called push.

Stack interfaces implement a peek operation for examining the element at the top of the stack.

A Python list structure and its methods implement a stack perfectly.

In a linked structure stack implementation, efficient pushing and popping require adding and removing of nodes at the head of the linked sequence.

Basic Python Programming

An Overview of Collections

Searching, Sorting, and Complexity Analysis

Arrays and Linked Structures

Interfaces, Implementations, and Polymorphism

Inheritance and Abstract Classes

Queues

Lists

Trees

Sets and Dictionaries

Graphs

Filters

Exam 7: Stacks

Which of the following is NOT an operation supported by a stack interface?

In the algorithm to evaluate a postfix expression, what does the algorithm do when an operator is encountered?

In the algorithm to evaluate a postfix expression, what does the algorithm do when an operand is encountered?

When using a stack to evaluate the balance of brackets and parentheses in an expression, what is the final step?

The first step in evaluating a postfix expression is to scan the expression from left to right.

In the algorithm that checks for a balanced expression, which of the following is true if a closing bracket is encountered?

Using a stack is a good approach to determining if the use of brackets in an expression is balanced.

Addition and subtraction have higher precedence when evaluating an infix expression.

The time complexity of the postfix expression evaluation algorithm is O( n2 ) .

Which of the following is NOT an application of stacks in computer science?

What is the function of the peek method in a stack implementation?

To avoid stack overflow, the stack algorithm should raise an error if an item is added to a full stack.

When evaluating an arithmetic expression, first you transform it from its postfix form to its infix form.

When converting from infix form to postfix form, parentheses are added to the equation.

What is the operation that adds items to a stack?

The Node class for use in the linked structure stack contains three fields: data, next, and previous.

The operation for removing an item from the stack is called push.

Stack interfaces implement a peek operation for examining the element at the top of the stack.

A Python list structure and its methods implement a stack perfectly.

In a linked structure stack implementation, efficient pushing and popping require adding and removing of nodes at the head of the linked sequence.

Basic Python Programming

An Overview of Collections

Searching, Sorting, and Complexity Analysis

Arrays and Linked Structures

Interfaces, Implementations, and Polymorphism

Inheritance and Abstract Classes

Queues

Lists

Trees

Sets and Dictionaries

Graphs

Filters

The time complexity of the postfix expression evaluation algorithm is O( n² ) .