Statewalk
Watch the state until it makes sense.
Interactive essays for understanding systems.
Cover
Building a heap, from the bottom up
A min-heap is built by repairing a sequence of local promises, starting at the last parent.
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02Red and blue on a closed interval
Binary search is not about finding a value. It is about locating the partition point where a predicate turns from false to true.
Read03Keeping a join alive, one row at a time
Four relations in a chain. A row is live when it can reach the bottom of the chain, and only the top of the chain ever emits a number.
Read04Monotonic stacks: let the future resolve the past
A next-greater element is not a search for every position. It is a queue of unresolved promises, settled once by the first larger value.
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