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Stop Guessing
How Much to Practice

Our algorithm calculates exactly when and how many times to review each problem—based on your actual performance.

No more random grinding. No more forgetting before interviews.

The Problem with Traditional Practice

Without a system, you forget 80% of what you learn within a week. Random problem selection leaves weak patterns untouched.

Based on Ebbinghaus's forgetting curve research (1885)

MemoryDay 1Day 3Day 7Day 3020%90%
Random practice
With CodeSparring
Research-Backed

Built on 40 Years of Cognitive Science

Four proven learning principles, applied to your interview prep.

10-30%
Better Retention

Spacing Effect

Distributed practice beats cramming. Our algorithm spaces your reviews for optimal long-term retention.

Cepeda et al., 2006Psychological Bulletin

50%
Better Retention

Testing Effect

Active recall strengthens memory more than passive review. Every practice session is a retrieval opportunity.

Roediger & Karpicke, 2006Psychological Science

43%
Better Retention

Interleaving

Mixing different patterns daily improves transfer to new problems. We intelligently vary your practice.

Rohrer & Taylor, 2007Instructional Science

Optimal
Better Retention

Forgetting Curve

Review at 70-80% retention for maximum efficiency. Our algorithm knows exactly when you're about to forget.

Ebbinghaus, 1885Memory: A Contribution to Experimental Psychology

LeetCode Gives You Problems
We Give You a System

Feature
CodeSparring
LeetCode
Personalized practice schedule
Knows when you'll forget
AI-powered review timing
Pattern-specific decay tracking
Interview countdown optimization
Science-backed spaced repetition
Smart notification system
Large problem database
Personalized Roadmaps

Your Interview
Your Timeline

Tell us your interview date, target company, and current level. Get a day-by-day plan optimized for your success.

Customized to your target company's patterns
Adapts based on your performance
Prioritizes weak areas automatically
Accounts for forgetting curve science
Your Roadmap
Google L4 Interview
28 days
Week 1
Arrays & Hashing
Week 2In Progress
Two Pointers & Sliding Window
Week 3
Trees & Graphs
Week 4
Dynamic Programming
Smart Notifications

10 Types of Intelligent Alerts

Never miss the optimal moment to practice.

Spaced Review
Pattern Decay
Daily Reminder
Streak Alert
Interview Countdown
Milestone
Weak Pattern
Roadmap Update
Optimal Time
Rest Reminder

3 Steps to Interview Success

01

Create Your Roadmap

Enter your interview date and target company. Our AI generates your personalized study plan.

02

Practice Smart

Follow daily recommendations. We track your performance and optimize review timing.

03

Ace Your Interview

Arrive confident with patterns deeply embedded in long-term memory.

Scientific References

Spacing Effect

Cepeda, N.J., et al. (2006). Distributed practice in verbal recall tasks: A review and quantitative synthesis. Psychological Bulletin, 132(3), 354-380.

Testing Effect

Roediger, H.L., & Karpicke, J.D. (2006). Test-enhanced learning. Psychological Science, 17(3), 249-255.

Interleaving

Rohrer, D., & Taylor, K. (2007). The shuffling of mathematics problems improves learning. Instructional Science, 35(6), 481-498.

Forgetting Curve

Ebbinghaus, H. (1885). Memory: A Contribution to Experimental Psychology. Teachers College, Columbia University.

Sleep Consolidation

Walker, M.P. (2017). Why We Sleep: Unlocking the Power of Sleep and Dreams. Scribner.

SM-2 Algorithm

Wozniak, P.A., & Gorzelanczyk, E.J. (1994). Optimization of repetition spacing in the practice of learning. Acta Neurobiologiae Experimentalis, 54, 59-62.

Ready to Practice Smarter?

Join the future of interview prep with science-backed learning.

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