WRITING
Notes on building and running systems
Engineering write-ups — architecture, security, and the occasional war story.
#sorting · All writing
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- #leetcode 50
- #array 13
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- #hash-table 6
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01
K Closest Points to Origin: sorting, min heap, and when to use a bounded max heap
Three approaches to finding the k nearest points — full sort, min heap, and the bounded max heap that cuts memory from O(n) to O(k). The bounded version is what I'd actually ship in production.Jun 14, 2026 · 10 min read · #00039
02
3Sum: two pointers inside a sorted loop
3Sum takes Two Sum II one level up: fix one element, then run Two Sum II on the rest. Sorting first lets you skip duplicates cleanly, which is the tricky part most implementations get wrong.Jun 13, 2026 · 12 min read · #00014
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