Question
Implement a mutable range-sum structure. Given an initial array `nums` and a list of operations `ops`, process them in order: `["u", i, val]` sets index i to val (point assignment), and `["q", l, r]` asks for the inclusive sum over [l, r]. Return the list of answers to the query operations, in order. Both updates and queries must run in O(log n). `0 <= len(nums) <= 100000`, `len(ops) <= 100000`.
segtree_sum_ops(nums: list[int], ops: list[list]) → list[int][[1,3,5,7,9,11],[["q",1,3],["u",1,10],["q",1,3]]]out[15,22]State your approach and its time/space complexity out loud before you optimize. Handle the edge cases (empty input, duplicates, overflow), and say why you chose this over the brute force. Green tests are the floor, not the grade.
Vibe coding: describe the solution in plain language (or narrate it) and the coach grades your approach. Generating runnable code from your description is coming next.