Queue Concept and FIFO Principle in DSA Python - Build from Scratch

Queue Concept and FIFO Principle

📖 Scenario: Imagine a line of people waiting to buy tickets at a movie theater. The first person to get in line is the first person to get the ticket and leave the line. This is called FIFO - First In, First Out.

🎯 Goal: You will create a simple queue using a list in Python. You will add people to the queue and then remove them in the order they arrived, showing how FIFO works.

📋 What You'll Learn

Create a list called queue with three people in order: 'Alice', 'Bob', and 'Charlie'

Create a variable called new_person and set it to 'Diana'

Add new_person to the end of the queue

Remove the first person from the queue to simulate them getting the ticket

Print the final state of the queue showing the order of people still waiting

💡 Why This Matters

🌍 Real World

Queues are used in real life whenever people or things wait in line, like at banks, supermarkets, or call centers.

💼 Career

Understanding queues helps in programming tasks like managing tasks, handling requests, or processing data in order.

1

Create the initial queue

Create a list called queue with these exact people in order: 'Alice', 'Bob', and 'Charlie'

DSA Python

# Create the queue list with 'Alice', 'Bob', and 'Charlie'
# Your code here

Hint

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

2

Add a new person to the queue

Create a variable called new_person and set it to 'Diana'

DSA Python

queue = ['Alice', 'Bob', 'Charlie']
# Create a variable new_person and set it to 'Diana'
# Your code here

Hint

Use the equals sign = to assign the string 'Diana' to new_person.

3

Add the new person to the end of the queue

Use the append() method on queue to add new_person to the end

DSA Python

queue = ['Alice', 'Bob', 'Charlie']
new_person = 'Diana'
# Add new_person to the end of queue
# Your code here

Hint

Use queue.append(new_person) to add the new person at the end.

4

Remove the first person from the queue and print the result

Remove the first person from queue using pop(0) to simulate them getting the ticket, then print the final queue

DSA Python

queue = ['Alice', 'Bob', 'Charlie']
new_person = 'Diana'
queue.append(new_person)
# Remove the first person from queue and print the queue
# Your code here

Hint

Use queue.pop(0) to remove the first person, then print(queue) to show the remaining people.