{ "data": { "question": { "questionId": "2626", "questionFrontendId": "2537", "boundTopicId": null, "title": "Count the Number of Good Subarrays", "titleSlug": "count-the-number-of-good-subarrays", "content": "

Given an integer array nums and an integer k, return the number of good subarrays of nums.

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A subarray arr is good if it there are at least k pairs of indices (i, j) such that i < j and arr[i] == arr[j].

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A subarray is a contiguous non-empty sequence of elements within an array.

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Example 1:

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\nInput: nums = [1,1,1,1,1], k = 10\nOutput: 1\nExplanation: The only good subarray is the array nums itself.\n
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Example 2:

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\nInput: nums = [3,1,4,3,2,2,4], k = 2\nOutput: 4\nExplanation: There are 4 different good subarrays:\n- [3,1,4,3,2,2] that has 2 pairs.\n- [3,1,4,3,2,2,4] that has 3 pairs.\n- [1,4,3,2,2,4] that has 2 pairs.\n- [4,3,2,2,4] that has 2 pairs.\n
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Constraints:

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