Day 21/365: Weekly Contest/Review -- DSA & System Design

365 Day DSA & System Design Challenge

Day 21 was about making the weekly contest useful.

What I wanted clear today:

• timed medium problems expose what actually survives pressure
• misses are often process failures, not just topic failures
• review should diagnose the miss instead of only recording the score
• the mistake log matters more than the headline result
• next week's plan should come from repeated failure patterns

The biggest shift was treating the contest as a diagnostic. Timed practice showed where pattern recall, invariant design, and edge-case handling still break down. The review pass turned those misses into labels I can use next week.

That made Day 21 feel much more practical than a generic review session. The score was temporary. The diagnosis was reusable.

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Day 21/365 of the 365 Day DSA & System Design Challenge.