{ "data": { "question": { "questionId": "2870", "questionFrontendId": "2765", "boundTopicId": null, "title": "Longest Alternating Subarray", "titleSlug": "longest-alternating-subarray", "content": "

You are given a 0-indexed integer array nums. A subarray s of length m is called alternating if:

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Return the maximum length of all alternating subarrays present in nums or -1 if no such subarray exists.

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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 = [2,3,4,3,4]\nOutput: 4\nExplanation: The alternating subarrays are [3,4], [3,4,3], and [3,4,3,4]. The longest of these is [3,4,3,4], which is of length 4.\n
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Example 2:

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\nInput: nums = [4,5,6]\nOutput: 2\nExplanation: [4,5] and [5,6] are the only two alternating subarrays. They are both of length 2.\n
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Constraints:

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

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Python 2.7.12.

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C# 10 with .NET 6 runtime

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