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 = 4 Output: 12.75 Explanation: 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) {
if(nums.Length<k){
return 0;
}
int sum = 0;
//sum of first k nums in sliding window
for(int i=0;i<k;i++){
sum+=nums[i];
}
int max = sum;
//calculate maximum sum window
for(int i=1;i<nums.Length-k+1;i++){
sum-=nums[i-1];
sum+=nums[i+k-1];
if(max<sum){
max = sum;
}
}
return (double)max/k;
}
}
Time Complexity: O(n)
Space Complexity: O(k)


