Master Big O Notation with Interactive Practice

Learn to analyze time complexity like a pro. Practice with real code examples, get instant feedback, and build the skills you need to ace technical interviews.

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What You'll Practice

Our practice tool covers all the essential time complexity patterns you need to know for analyzing algorithms and preparing for technical interviews.

O(1) - Constant time operations
O(log n) - Binary search and divide-and-conquer
O(n) - Linear iterations and single loops
O(n log n) - Efficient sorting algorithms
O(n²) - Nested loops and quadratic algorithms
O(2ⁿ) - Recursive exponential algorithms

Why Practice Big O Notation?

Real Code Examples

Practice with actual code snippets from real-world scenarios, not theoretical examples.

Instant Feedback

Get immediate explanations when you answer, helping you learn from mistakes quickly.

Adaptive Difficulty

ELO-based system adjusts problem difficulty based on your performance.

Track Progress

Monitor your improvement with statistics on problems solved and skill rating.

Interview Preparation

Build confidence analyzing time complexity for technical interviews.

Free Forever

No subscriptions, no paywalls. Practice as much as you want, completely free.

How the Practice Tool Works

1

Read the Code

You're presented with a code snippet in JavaScript, Python, or Java

2

Analyze Complexity

Identify the time complexity from multiple choice options

3

Get Feedback

Receive instant explanation of the correct answer and why

4

Track Progress

Watch your ELO rating improve as you solve more problems

Ready to Start Practicing?

Start practicing and improve your Big O notation skills

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Frequently Asked Questions

What is Big O notation?

Big O notation is a mathematical way to describe how an algorithm's runtime or space requirements grow as the input size increases. It helps developers understand and compare algorithm efficiency.

Why is learning Big O important?

Understanding Big O notation is essential for writing efficient code and is a common topic in technical interviews at major tech companies. It helps you make better decisions about which algorithms and data structures to use.

Do I need programming experience?

Basic programming knowledge is helpful. You should be familiar with concepts like loops, functions, and basic data structures. Our practice tool shows code in multiple languages including JavaScript, Python, and Java.

How does the practice tool work?

You're shown a code snippet and asked to identify its time complexity. After answering, you receive instant feedback with a detailed explanation. The difficulty adapts to your skill level using an ELO rating system.

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Big O Academy