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intermediate · order 86

Subarray sum equals k

hash-subarray-01Related book chapters: 16 (optional — this page is complete on its own)prefixHashMap

Slug: hash-subarray-01 · Paired reading: Chapter 16

Prompt

fn subarray_sum(nums: &[i32], k: i32) -> i32 — count contiguous subarrays summing to k. Prefix sums + frequency map.