35: Maximum average subarray

Given an array of integers, find the contiguous subarray of length k which has the largest average sum, return its average sum

 

Example 1

Input:  array = [-4, 1, 2, -3, 1], k = 2

Output: 1.5

Explanation: [1, 2] is the subarray with the largest average sum 1.5

Example 2

Input: [1, 1, 2, 5], k = 2

Output: 3.5