Stacks Fundamentals and Operations
28 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What does 'LIFO' stand for in the context of stacks?

  • Linear Input, First Out
  • Last Iteration, First Output
  • Last In, First Out (correct)
  • List Input, First Output

Elements in a stack can be added to and removed from both ends.

False (B)

What operation is used to retrieve the top element of a stack without removing it?

peek

To add an element to the top of the stack, the operation used is called _______.

<p>push</p> Signup and view all the answers

Which of the following is NOT a basic operation of a stack?

<p>enqueue (B)</p> Signup and view all the answers

Match the following stack operations with their descriptions:

<p>Push = Adds an element to the top of the stack Pop = Removes an element from the top of the stack Peek = Retrieves the top element of the stack IsEmpty = Determines if the stack is empty</p> Signup and view all the answers

In an array implementation of a stack, what value is set to the 'top' when the stack is empty?

<p>-1</p> Signup and view all the answers

In the array implementation of a stack, it is possible to push an element when the stack has reached its maximum size.

<p>False (B)</p> Signup and view all the answers

What is the final result of the postfix expression '10 2 8 * + 3 -'?

<p>-2 (A)</p> Signup and view all the answers

In postfix evaluation, numbers are pushed onto the stack while operators are popped from the stack.

<p>True (A)</p> Signup and view all the answers

What is the first step when evaluating a postfix expression?

<p>Create a stack to store operands.</p> Signup and view all the answers

In the expression '7 4 -3 * 1 5 + / *', the first operation evaluated is the one involving ______.

<p>-3</p> Signup and view all the answers

Match the following expressions with their evaluation methods:

<p>10 + 2 * 8 - 3 = Postfix Conversion 7 4 -3 * 1 5 + / * = Postfix Evaluation</p> Signup and view all the answers

What operation is performed to add an element to the top of the stack?

<p>Push (C)</p> Signup and view all the answers

Popping an element from a stack will remove the last element added.

<p>False (B)</p> Signup and view all the answers

What is a common application of stacks?

<p>Reversing a string</p> Signup and view all the answers

In the stack implementation, the pointer named ______ points to the top of the stack.

<p>top</p> Signup and view all the answers

What does the 'push' function do when the stack is empty?

<p>Sets the new node as the top of the stack (D)</p> Signup and view all the answers

A stack can be implemented using a doubly linked list.

<p>True (A)</p> Signup and view all the answers

In what order do elements come out when popping from a stack?

<p>Last In First Out (LIFO)</p> Signup and view all the answers

What is the resultant postfix expression for the infix expression (A+B)*(C-D)?

<p>AB+CD-* (A)</p> Signup and view all the answers

In postfix notation, the order of operations is not preserved compared to infix notation.

<p>False (B)</p> Signup and view all the answers

What action is taken when encountering a right parenthesis?

<p>Pop all contents of the stack until the left parenthesis is popped.</p> Signup and view all the answers

If the reading symbol is an operator, it is pushed onto the stack after popping any operator with ______ precedence.

<p>higher or equal</p> Signup and view all the answers

Match the symbols with their actions in infix to postfix conversion:

<p>Operand = Directly print to result Left Parenthesis '(', = Push to Stack Right Parenthesis ')' = Pop from Stack until left parenthesis Operator = Push to Stack after checking precedence</p> Signup and view all the answers

What happens when the reading symbol is an operand?

<p>It is directly printed to the result. (C)</p> Signup and view all the answers

The left parenthesis is included in the results when popping from the stack.

<p>False (B)</p> Signup and view all the answers

In the expression 10 + 2 * 8 - 3, what operation takes place when the operator - is encountered?

<p>Pop + and * because they have higher priority.</p> Signup and view all the answers

Flashcards

Stack

A list where insertions and deletions are done at the same end (LIFO - Last-In, First-Out).

Stack Operations

Add (push), remove (pop), see top (peek), check if empty (isEmpty), see size of the stack

Push

Adding an element to the top of the stack.

Pop

Removing an element from the top of the stack.

Signup and view all the flashcards

Peek

Viewing the element at the top of the stack without removing it.

Signup and view all the flashcards

Stack Implementation (Array)

Using an array to store stack elements, with a variable top to track the position of the topmost element.

Signup and view all the flashcards

Array Stack - Push

Increments 'top' and places new data at stack[top].

Signup and view all the flashcards

Array Stack - Pop

Retrieves data from stack[top] and decrements 'top'.

Signup and view all the flashcards

Infix to Postfix Conversion

A way to convert mathematical expressions from their standard notation (e.g., 1 + 2) to a form that's easier for computers to evaluate (e.g., 1 2 +).

Signup and view all the flashcards

Postfix Expression Evaluation

Evaluating a mathematical expression written in postfix notation. Operands are pushed onto a stack, and operators are applied to the top operands.

Signup and view all the flashcards

Postfix Notation

A way of writing mathematical expressions where the operator follows its operands.

Signup and view all the flashcards

Stack in Postfix Evaluation

A temporary storage area for operands in the evaluation process.

Signup and view all the flashcards

Operand in Postfix Evaluation

A number or a variable in an expression that's operated on by the operator.

Signup and view all the flashcards

Operand

A numerical value or variable in an arithmetic expression.

Signup and view all the flashcards

Operator Precedence

The order in which operators are evaluated; operators with higher precedence are evaluated before those with lower precedence.

Signup and view all the flashcards

Left Parenthesis '('

Indicates the start of a sub-expression; pushed onto the stack.

Signup and view all the flashcards

Right Parenthesis ')'

Indicates the end of a sub-expression; operators are popped from the stack until the matching left parenthesis is found.

Signup and view all the flashcards

Operator

A symbol that performs an operation on operands, e.g., +, -, *, /.

Signup and view all the flashcards

Linked List Stack Implementation

A stack data structure implemented using a linked list, where all operations (push, pop) occur at the top of the stack.

Signup and view all the flashcards

Stack Push Operation

Adding an element to the top of the stack by inserting a new node at the beginning of the linked list.

Signup and view all the flashcards

Stack Pop Operation

Removing an element from the top of the stack by deleting the node at the beginning and returning its data.

Signup and view all the flashcards

Stack - Top

A pointer to the topmost node of the linked list in the stack.

Signup and view all the flashcards

Reversing Strings

An application of stacks where characters are pushed onto a stack and then popped off, resulting in the reversed string.

Signup and view all the flashcards

Stack Applications

Stacks are useful for tasks like managing function calls, handling undo/redo operations, and evaluating expressions.

Signup and view all the flashcards

Stack Data Structure

A linear data structure that follows the Last-In, First-Out (LIFO) principle.

Signup and view all the flashcards

Study Notes

Stacks

  • Stacks are lists with insertions and deletions occurring at the same end.
  • Last-In, First-Out (LIFO) is the principle behind stacks.
  • Elements are removed in the reverse order of insertion.
  • Additions and deletions only happen at the top of the stack.

Basic Stack Operations

  • add (push): Adding an element to the top of the stack.
  • remove (pop): Removing the top element from the stack.
  • peek/top: Retrieving the top element (without removing it).
  • isEmpty: Checks if the stack is empty.
  • size: Counts the number of elements in the stack.

Stack Implementation

  • Using Array:
    • Requires a fixed-size array.
    • MAXSIZE is the array's size.
    • top variable tracks the top element's index.
    • top = -1 initializes an empty stack.
  • Using Linked List:
    • Dynamically allocates memory.
    • top pointer refers to the top element.
    • Top element is at the beginning of the linked list.
    • Pushing inserts at the beginning.
    • Popping removes from beginning.

Pushing and Popping

  • Pushing:
    • Increments top.
    • Stores the new element at stack[top].
  • Popping:
    • Gets the element at stack[top].
    • Decrements top.

Stacks Applications

  • Line Editing:
  • Reversing Strings: Push characters left to right, pop right to left.
  • Bracket Matching: Use a stack to check matching brackets.
  • Postfix Calculation: Evaluate expressions using a stack.
  • Function Call Stack: Track function calls.
  • Browsers: Navigate back/forward through visited pages.
  • Infix to Postfix Conversion: Convert expressions for evaluation. Rules for conversion are based on precedence and order of operators.
  • Evaluating Postfix Expressions: Evaluate expressions in postfix notation. Operators are evaluated using the top two values stored.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team

Related Documents

Lecture 4 - Stacks PDF

Description

This quiz covers the fundamentals of stacks, focusing on the Last-In, First-Out (LIFO) principle. You will explore basic stack operations such as push, pop, and peek, as well as understand stack implementation using arrays and linked lists.

More Like This

Stack Operations Pretest Quiz
5 questions

Stack Operations Pretest Quiz

CompatiblePeridot avatar
CompatiblePeridot
Stack Operations Overview
5 questions

Stack Operations Overview

SuitableVariable avatar
SuitableVariable
Basic Stack Operations Quiz
9 questions

Basic Stack Operations Quiz

SmartWhite avatar
SmartWhite
Stack Data Structure Overview
21 questions

Stack Data Structure Overview

InstructiveWave169 avatar
InstructiveWave169
Use Quizgecko on...
Browser
Open
Browser
Browser