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Applied Coding & Editor Primitives1 / 2

1 min lesson

A 45-minute mental template

Rebuild the sequence in "A 45-minute mental template" from memory, ending with the check that proves the outcome.

Step 1 of 2

A 45-minute mental template

  1. 1Contract (2 min). Write the typed signature and a one-line constraint, restate aloud.
  2. 2Brute force (5 min). Get a correct, obvious version working; name its complexity.
  3. 3Optimize (15 min). Apply the size-before-hash / right-to-left / BFS insight; keep it readable.
  4. 4Edge cases (8 min). Empty, single, overlapping, out-of-range - assert each.
  5. 5Walk it (rest). Trace one input end to end out loud, then state what you'd test next with more time.
Watch out

Don't gold-plate the type system. Elaborate conditional types or branded generics burn time and rarely earn points in a 45-minute screen. Clean, obvious types that compile cleanly win; clever types that you spend ten minutes debugging lose.