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 = 4Output: 12.75Explanation: Maximum average is (12-5-6+50)/4 = 51/4 = 12.75

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

public class Solution {      public double findMaxAverage(int[] nums, int k) {          double cur = 0.0;          for (int i = 0; i < k; ++i)              cur += nums[i];          double max = cur;          for (int i = k; i < nums.length; ++i) {              cur = cur + nums[i] - nums[i - k];              max = Math.max(max, cur);          }          return max / k;      }  }