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intermediate · order 83

Two-sum with a HashMap

hash-two-sum-01Related book chapters: 16 (optional — this page is complete on its own)HashMaptwo-sum

Slug: hash-two-sum-01 · Paired reading: Chapter 16

Prompt

fn two_sum(nums: &[i32], target: i32) -> Option<(usize, usize)> — unsorted; return first pair of indices that sum to target. One pass with a map.