{ "data": { "question": { "questionId": "1620", "questionFrontendId": "1497", "boundTopicId": null, "title": "Check If Array Pairs Are Divisible by k", "titleSlug": "check-if-array-pairs-are-divisible-by-k", "content": "

Given an array of integers arr of even length n and an integer k.

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We want to divide the array into exactly n / 2 pairs such that the sum of each pair is divisible by k.

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Return true If you can find a way to do that or false otherwise.

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Example 1:

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\nInput: arr = [1,2,3,4,5,10,6,7,8,9], k = 5\nOutput: true\nExplanation: Pairs are (1,9),(2,8),(3,7),(4,6) and (5,10).\n
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Example 2:

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\nInput: arr = [1,2,3,4,5,6], k = 7\nOutput: true\nExplanation: Pairs are (1,6),(2,5) and(3,4).\n
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Example 3:

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\nInput: arr = [1,2,3,4,5,6], k = 10\nOutput: false\nExplanation: You can try all possible pairs to see that there is no way to divide arr into 3 pairs each with sum divisible by 10.\n
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Constraints:

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