643. Maximum Average Subarray I

You are given an integer array nums consisting of n elements, and an integer k.

Find a contiguous subarray whose length is equal to k that has the maximum average value and return this value. Any answer with a calculation error less than 10-5 will be accepted.

 

Example 1:

Input: nums = [1,12,-5,-6,50,3], k = 4
Output: 12.75000
Explanation: Maximum average is (12 - 5 - 6 + 50) / 4 = 51 / 4 = 12.75

Example 2:

Input: nums = [5], k = 1
Output: 5.00000

 

Constraints:

• n == nums.length
• 1 <= k <= n <= 105
• -104 <= nums[i] <= 104

---

class Solution:
    def findMaxAverage(self, nums: List[int], k: int) -> float:
        count=0
        left=0
        right=k-1
        for i in range(k):
            count += nums[i]
        ans=count
        for i in range(len(nums)-k):
            count-=nums[left]
            left+=1
            right+=1
            count+=nums[right]
            ans=max(ans,count)
        return ans/k