📜 WAYPOINT LESSON
Checkpoint — The Structure the Budget Names
⭐⭐⭐ advanced⏳ 25 min read📍 Lesson 212 of 281
Point-set + prefix-sum at full scale: the constraint table admits exactly one family. The W is the honest-looking O(p) re-sum.
Checkpoint — The Structure the Budget Names. n = q = 200000 interleaved sets and prefix asks. The budget law kills re-summing (~10^10 ops) and leaves exactly one comfortable family. Note the folded "X S" checksum on the full-scale test: it verifies the whole answer stream, not just a line — the standard trick used throughout this course's big tests.