{ "data": { "question": { "questionId": "2301", "questionFrontendId": "2183", "boundTopicId": null, "title": "Count Array Pairs Divisible by K", "titleSlug": "count-array-pairs-divisible-by-k", "content": "

Given a 0-indexed integer array nums of length n and an integer k, return the number of pairs (i, j) such that:

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Example 1:

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\nInput: nums = [1,2,3,4,5], k = 2\nOutput: 7\nExplanation: \nThe 7 pairs of indices whose corresponding products are divisible by 2 are\n(0, 1), (0, 3), (1, 2), (1, 3), (1, 4), (2, 3), and (3, 4).\nTheir products are 2, 4, 6, 8, 10, 12, and 20 respectively.\nOther pairs such as (0, 2) and (2, 4) have products 3 and 15 respectively, which are not divisible by 2.    \n
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Example 2:

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\nInput: nums = [1,2,3,4], k = 5\nOutput: 0\nExplanation: There does not exist any pair of indices whose corresponding product is divisible by 5.\n
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Constraints:

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Most standard library headers are already included automatically for your convenience.

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OpenJDK 17. Java 8 features such as lambda expressions and stream API can be used.

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Most standard library headers are already included automatically for your convenience.

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Python 2.7.12.

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