8/8 每日一題(找出連續k個子數列的最大平均)

 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:

        if len(nums)==k:

            return sum(nums)/k

        max_sum=sum(nums[:k])

        curr_sum=max_sum  

       

        for i in range(k,len(nums)):

            max_sum=max_sum+nums[i]-nums[i-k] #指針持續移動

            curr_sum=max(max_sum,curr_sum)  

       

 

        return curr_sum/k