Stack operations (push, pop, peek) in Data Structures Theory - Mini Project: Build & Apply

Stack operations (push, pop, peek)

📖 Scenario: Imagine you have a stack of books on your desk. You can only add a book on top, remove the top book, or look at the top book without removing it. This is how a stack data structure works in computer science.

🎯 Goal: You will build a simple stack using a list and perform the basic stack operations: push (add a book), pop (remove the top book), and peek (see the top book).

📋 What You'll Learn

Create a list called stack with initial books

Create a variable called new_book to add to the stack

Write code to push new_book onto stack

Write code to pop the top book from stack and store it in top_book

Write code to peek at the top book of stack and store it in peek_book

💡 Why This Matters

🌍 Real World

Stacks are used in real life for things like stacking plates, undo features in software, and managing tasks in order.

💼 Career

Understanding stack operations is important for programming jobs, especially in areas like software development, algorithms, and system design.

1

Create the initial stack

Create a list called stack with these exact books in order: 'Math', 'Science', 'History'.

Data Structures Theory

# Create the initial stack list with the books
# Your code here

Need a hint?

Use square brackets [] to create a list and separate items with commas.

2

Add a new book to the stack

Create a variable called new_book and set it to the string 'English'.

Data Structures Theory

stack = ['Math', 'Science', 'History']
# Create a variable new_book with value 'English'
# Your code here

Need a hint?

Assign the string 'English' to the variable new_book.

3

Push the new book onto the stack

Use the append() method on stack to add the new_book to the top of the stack.

Data Structures Theory

stack = ['Math', 'Science', 'History']
new_book = 'English'
# Add new_book to stack using append()
# Your code here

Need a hint?

Use stack.append(new_book) to add the book on top.

4

Pop and peek the stack

Remove the top book from stack using pop() and store it in top_book. Then, get the current top book without removing it by accessing the last item of stack and store it in peek_book.

Data Structures Theory

stack = ['Math', 'Science', 'History']
new_book = 'English'
stack.append(new_book)
# Remove the top book and store in top_book
# Get the current top book and store in peek_book
# Your code here

Need a hint?

Use pop() to remove the last item and stack[-1] to peek at the last item.