Array Rotation Techniques in DSA Python - Build from Scratch

Array Rotation Techniques

📖 Scenario: Imagine you have a list of daily tasks arranged in order. Sometimes, you want to start your day from a different task but keep the order of the remaining tasks the same. This is like rotating the list of tasks.

🎯 Goal: You will create a program that rotates an array (list) to the left by a given number of positions. This means the first few tasks move to the end, and the rest shift forward.

📋 What You'll Learn

Create a list called tasks with exact values: ['Email', 'Meeting', 'Coding', 'Lunch', 'Review']

Create a variable called rotate_by and set it to 2

Write code to rotate the tasks list to the left by rotate_by positions

Print the rotated list exactly as a Python list

💡 Why This Matters

🌍 Real World

Rotating lists is useful in scheduling, games, and data processing where order changes but elements stay the same.

💼 Career

Understanding array rotation helps in coding interviews and tasks involving data manipulation and optimization.

1

Create the initial list of tasks

Create a list called tasks with these exact values in order: 'Email', 'Meeting', 'Coding', 'Lunch', 'Review'

DSA Python

# Create the list called tasks with the given values
# Your code here

Hint

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

2

Set the number of positions to rotate

Create a variable called rotate_by and set it to the number 2

DSA Python

tasks = ['Email', 'Meeting', 'Coding', 'Lunch', 'Review']
# Create rotate_by variable and set it to 2
# Your code here

Hint

Just assign the number 2 to the variable rotate_by.

3

Rotate the list to the left by rotate_by positions

Create a new list called rotated_tasks that contains the tasks list rotated to the left by rotate_by positions using slicing

DSA Python

tasks = ['Email', 'Meeting', 'Coding', 'Lunch', 'Review']
rotate_by = 2
# Create rotated_tasks by slicing tasks to rotate left by rotate_by
# Your code here

Hint

Use list slicing: tasks[rotate_by:] gets the part after the first rotate_by items, and tasks[:rotate_by] gets the first rotate_by items.

4

Print the rotated list

Print the rotated_tasks list exactly as a Python list

DSA Python

tasks = ['Email', 'Meeting', 'Coding', 'Lunch', 'Review']
rotate_by = 2
rotated_tasks = tasks[rotate_by:] + tasks[:rotate_by]
# Print rotated_tasks
# Your code here

Hint

Use print(rotated_tasks) to show the rotated list.