Slug: arr-chunks-01 · Paired reading: Chapter 15
Prompt
fn pair_sums(a: &[i32]) -> Vec<i32> — sums of non-overlapping pairs
via chunks_exact(2) (drop a trailing singleton).
fn triple_products(a: &[i32]) -> Vec<i32> — products of every
overlapping window of length 3 via windows(3).