#03MediumArrays & Strings · 52% acceptance

Rolling Window Mean

Sliding WindowArrayMath

Given an array `nums` and an integer `k`, find the contiguous window of length `k` with the highest average value and return that average.

If you have ever smoothed a noisy time-series with a moving average, this is that — turned into an O(n) algorithm.

Examples

Input: nums = [1,12,-5,-6,50,3], k = 4

Output: 12.75

Note: The window [12,-5,-6,50] averages 12.75.

Constraints

·1 ≤ k ≤ nums.length ≤ 10^5
·-10^4 ≤ nums[i] ≤ 10^4

Hints

solution.pyPython 3

def max_window_mean(nums, k):
    window = sum(nums[:k])
    best = window
    for i in range(k, len(nums)):
        window += nums[i] - nums[i - k]
        best = max(best, window)
    return best / k

Test console

// hit Run to execute the sample tests

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