Maximum Average Subarray I

class Solution {
public:
    double findMaxAverage(vector<int>& nums, int k) {
        long long sum = 0;
        for (int i = 0; i < k; ++i) sum += nums[i];
        long long best = sum;
        for (int i = k; i < (int)nums.size(); ++i) {
            sum += nums[i] - nums[i - k];
            best = max(best, sum);
        }
        return (double)best / k;
    }
};

func findMaxAverage(nums []int, k int) float64 {
    var sum int64
    for i := 0; i < k; i++ {
        sum += int64(nums[i])
    }
    best := sum
    for i := k; i < len(nums); i++ {
        sum += int64(nums[i] - nums[i-k])
        if sum > best {
            best = sum
        }
    }
    return float64(best) / float64(k)
}

from typing import List

class Solution:
    def findMaxAverage(self, nums: List[int], k: int) -> float:
        s = sum(nums[:k])
        best = s
        for i in range(k, len(nums)):
            s += nums[i] - nums[i - k]
            if s > best:
                best = s
        return best / k

function findMaxAverage(nums, k) {
    let sum = 0;
    for (let i = 0; i < k; i++) sum += nums[i];
    let best = sum;
    for (let i = k; i < nums.length; i++) {
        sum += nums[i] - nums[i - k];
        if (sum > best) best = sum;
    }
    return best / k;
}

class Solution {
    public double findMaxAverage(int[] nums, int k) {
        long sum = 0;
        for (int i = 0; i < k; i++) sum += nums[i];
        long best = sum;
        for (int i = k; i < nums.length; i++) {
            sum += nums[i] - nums[i - k];
            if (sum > best) best = sum;
        }
        return (double) best / k;
    }
}

function findMaxAverage(nums: number[], k: number): number {
    let sum = 0;
    for (let i = 0; i < k; i++) sum += nums[i];
    let best = sum;
    for (let i = k; i < nums.length; i++) {
        sum += nums[i] - nums[i - k];
        if (sum > best) best = sum;
    }
    return best / k;
}