README.md

643. Maximum Average Subarray I

Given an array consisting of n integers, find the contiguous subarray of given length k that has the maximum average value. And you need to output the maximum average value.

Example 1:

Input: [1,12,-5,-6,50,3], k = 4
Output: 12.75
Explanation: Maximum average is (12-5-6+50)/4 = 51/4 = 12.75

Note:

1. 1 <= k <= n <= 30,000.
2. Elements of the given array will be in the range [-10,000, 10,000].

Solutions (Rust)

1. Sliding Window

impl Solution {
    pub fn find_max_average(nums: Vec<i32>, k: i32) -> f64 {
        let k = k as usize;
        let mut sum: i32 = nums.iter().take(k).sum();
        let mut max_sum = sum;

        for i in k..nums.len() {
            sum += nums[i] - nums[i - k];
            max_sum = max_sum.max(sum);
        }

        max_sum as f64 / k as f64
    }
}