{ "data": { "question": { "questionId": "2915", "questionFrontendId": "2845", "boundTopicId": null, "title": "Count of Interesting Subarrays", "titleSlug": "count-of-interesting-subarrays", "content": "

You are given a 0-indexed integer array nums, an integer modulo, and an integer k.

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Your task is to find the count of subarrays that are interesting.

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A subarray nums[l..r] is interesting if the following condition holds:

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Return an integer denoting the count of interesting subarrays.

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Note: 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 = [3,2,4], modulo = 2, k = 1\nOutput: 3\nExplanation: In this example the interesting subarrays are: \nThe subarray nums[0..0] which is [3]. \n- There is only one index, i = 0, in the range [0, 0] that satisfies nums[i] % modulo == k. \n- Hence, cnt = 1 and cnt % modulo == k.  \nThe subarray nums[0..1] which is [3,2].\n- There is only one index, i = 0, in the range [0, 1] that satisfies nums[i] % modulo == k.  \n- Hence, cnt = 1 and cnt % modulo == k.\nThe subarray nums[0..2] which is [3,2,4]. \n- There is only one index, i = 0, in the range [0, 2] that satisfies nums[i] % modulo == k. \n- Hence, cnt = 1 and cnt % modulo == k. \nIt can be shown that there are no other interesting subarrays. So, the answer is 3.
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Example 2:

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\nInput: nums = [3,1,9,6], modulo = 3, k = 0\nOutput: 2\nExplanation: In this example the interesting subarrays are: \nThe subarray nums[0..3] which is [3,1,9,6]. \n- There are three indices, i = 0, 2, 3, in the range [0, 3] that satisfy nums[i] % modulo == k. \n- Hence, cnt = 3 and cnt % modulo == k. \nThe subarray nums[1..1] which is [1]. \n- There is no index, i, in the range [1, 1] that satisfies nums[i] % modulo == k. \n- Hence, cnt = 0 and cnt % modulo == k. \nIt can be shown that there are no other interesting subarrays. So, the answer is 2.
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Constraints:

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