K Radius Subarray Averages
You are given a 0-indexed array nums of n integers, and an integer k.
The k-radius average for a subarray of nums centered at some index i with the radius k is the average of all elements in nums between the indices i - k and i + k (inclusive). If there are less than k elements before or after the index i, then the k-radius average is -1.
Build and return an array avgs of length n where avgs[i] is the k-radius average for the subarray centered at index i.
The average of x elements is the sum of the x elements divided by x, using integer division. The integer division truncates toward zero, which means losing its fractional part.
- For example, the average of four elements
2,3,1, and5is(2 + 3 + 1 + 5) / 4 = 11 / 4 = 2.75, which truncates to2.
Example 1
Input
nums = [7,4,3,9,1,8,5,2,6], k = 3Output
[-1,-1,-1,5,4,4,-1,-1,-1]Indices 0, 1, and 2 have fewer than k elements before them, indices 6, 7, and 8 have fewer than k elements after them, and the centered radius-3 subarrays at indices 3, 4, and 5 have integer averages 5, 4, and 4.
Example 2
Input
nums = [100000], k = 0Output
[100000]With radius 0, the subarray centered at index 0 contains only 100000, so its average is 100000.
Constraints
- n == nums.length
- 1 <= n <= 10^5
- 0 <= nums[i], k <= 10^5