Given an integer array
nums and an integer
k, return the number of good subarrays of
arr is good if it there are at least
k pairs of indices
(i, j) such that
i < j and
arr[i] == arr[j].
A subarray is a contiguous non-empty sequence of elements within an array.
Input: nums = [1,1,1,1,1], k = 10 Output: 1 Explanation: The only good subarray is the array nums itself.
Input: nums = [3,1,4,3,2,2,4], k = 2 Output: 4 Explanation: There are 4 different good subarrays: - [3,1,4,3,2,2] that has 2 pairs. - [3,1,4,3,2,2,4] that has 3 pairs. - [1,4,3,2,2,4] that has 2 pairs. - [4,3,2,2,4] that has 2 pairs.
1 <= nums.length <= 105
1 <= nums[i], k <= 109