Week 10 Cold Revisit

This Friday, before any new work, re-solve four prior problems cold: no notes, no prior code open, no AI, the standard 25-minute struggle floor on each. The first solve taught the pattern; this blind re-solve is what makes it stick. This week’s obligation is larger than the usual two, because the week itself is lighter: one fixed problem plus three of your own choosing.

The problems

  1. Reorder List (Week 6, Linked List). https://leetcode.com/problems/reorder-list/
  2. Three problems of your choice from Weeks 5 to 8. Pick the ones you are least confident you could rebuild cold today. Weeks 5 to 8 cover Binary Search, Linked List, Trees, and Heap and Priority Queue, so draw from there. Choosing the ones that feel shakiest is the point; an easy re-solve teaches you nothing.

How to run the revisit

  • Do not look up which pattern any problem belongs to. Recognizing it cold, from the problem statement alone, is the entire point of the exercise; the tutor will not tell you.
  • Start each from a blank file. Name the pattern aloud, write the plain-English approach as a comment, then code.
  • Apply the 25-minute floor to each independently. If you stall past the floor, use the hint ladder, one rung per ask.
  • Submit each to LeetCode’s judge. The judge is the oracle, not the tutor.
  • Debrief each with the five questions in your commit message, and log the outcome in .tutor/revisit-log.md.

None of these is a trie or interval problem, and that is deliberate. The cold revisit trains recognition across the whole course, so the muscle you build is “read a cold statement and feel the pattern”, not “apply this week’s pattern again”. Reorder List in particular fuses three linked-list primitives (find the middle with fast/slow pointers, reverse the second half, then merge the two halves alternately), so it is a good test of whether those moves are still fluent. If any of the four comes back slower than you expect, that is the signal for where to spend your next stretch session.