Find All K-Distant Indices in an Array

Input: nums = [3,4,9,1,3,9,5], key = 9, k = 1

Output: [1,2,3,4,5,6]

Explanation: Here, nums[2] == key and nums[5] == key.

• For index 0, |0 - 2| > k and |0 - 5| > k, so there is no j where |0 - j| <= k and nums[j] == key. Thus, 0 is not a k-distant index.

• For index 1, |1 - 2| <= k and nums[2] == key, so 1 is a k-distant index.

• For index 2, |2 - 2| <= k and nums[2] == key, so 2 is a k-distant index.

• For index 3, |3 - 2| <= k and nums[2] == key, so 3 is a k-distant index.

• For index 4, |4 - 5| <= k and nums[5] == key, so 4 is a k-distant index.

• For index 5, |5 - 5| <= k and nums[5] == key, so 5 is a k-distant index.

• For index 6, |6 - 5| <= k and nums[5] == key, so 6 is a k-distant index.

Thus, we provide [1,2,3,4,5,6] which is sorted in increasing order.

Input: nums = [2,2,2,2,2], key = 2, k = 2

Output: [0,1,2,3,4]

Explanation: For all indices i in nums, there exists some index j such that |i - j| <= k and nums[j] == key, so every index is a k-distant index.

Hence, we provide [0,1,2,3,4].