Maximum Average Subarray I

Problem

Given nums and an integer k, find the contiguous subarray of length k with the maximum average, and return that average.

Examples

Constraints

1 ≤ k ≤ n ≤ 10⁵ · values in ±10⁴.

Attempt it first

This is the fixed-window lesson with a division tacked on at the end. The whole exercise is noticing that maximizing average is the same as maximizing sum (k is fixed, so dividing by it at the end doesn't change which window wins) — then applying the slide template directly.