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Code Drills
Patterns, complexity, and reading code under pressure — the technical screen, drilled from every angle.
0 done— accuracy
Solve
Read a problem, plan the approach, reveal the canonical solution.
79 problems
Write the Code
Type real Java or Python, then compare against the canonical.
79 problems
Pattern Triage
See a problem, name the pattern. Recognition only.
79 cards
Big O Quiz
Complexity of operations and structures — no code.
75 questions
Complexity Analysis
Read a snippet, name its time and space.
20 snippets
Algorithms
Dijkstra, MST, KMP, Fenwick — pick the right tool.
15 cards
Techniques
Scenario to production idiom: backoff, idempotency, leases.
72 questions
Code Review
Thirty lines. Find the race, the N+1, the injection.
15 reviews
Debugging
Function plus failing test. Find the bug.
15 bugs
Shuffle all 9 modes
$ drill code-drills --random