Learn to Read TheCode Signals
Master 50+ algorithm patterns by recognizing their key signals. Follow structured learning paths, take interactive quizzes, and ace your next coding interview with confidence.
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How Our Quizzes Work
Find Two Numbers That Add Up to Target
Given an array of integers and a target sum, return the indices of two numbers that add up to the target. You may assume each input has exactly one solution.
Which pattern would you use?
Correct! Hash Map is perfect here. The signal is "find pair that sums to target" - this screams complement lookup, which Hash Maps excel at.
Structured Learning Paths
Don't just memorize solutions—learn to recognize the signals that reveal which pattern to use. Our structured learning paths guide you from fundamentals to advanced topics with detailed explanations, complexity analysis, and curated practice problems.
50+ Algorithm Patterns
Organized by category and difficulty level
Deep-Dive Explanations
When to use, how it works, common pitfalls, and variations
Track Your Journey
Progress tracking from "Learning" to "Mastered"
Curated Practice Problems
Direct links to LeetCode problems for each pattern
Everything You Need to Master Patterns
Signal-Based Learning
Identify patterns by recognizing key "signals" in problem statements, just like in real interviews. No memorization required.
Track Your Progress
See your accuracy improve over time. Identify weak patterns and focus your practice where it matters most.
Spaced Repetition
Premium users get access to SRS features that help you remember patterns long-term with optimized review schedules.
Structured Learning Paths
Follow guided paths through 50+ patterns organized by difficulty. Track your progress from beginner to expert with visual indicators.
Instant Feedback
Get immediate explanations for every quiz question. Understand why each pattern is the right (or wrong) choice.
Mastery Tracking
Earn mastery levels (Novice → Expert) for each pattern. See your journey from beginner to master.
Ready to Master Algorithm Patterns?
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