{ "data": { "question": { "questionId": "3221", "questionFrontendId": "2951", "boundTopicId": null, "title": "Find the Peaks", "titleSlug": "find-the-peaks", "content": "

You are given a 0-indexed array mountain. Your task is to find all the peaks in the mountain array.

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Return an array that consists of indices of peaks in the given array in any order.

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Notes:

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Example 1:

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\nInput: mountain = [2,4,4]\nOutput: []\nExplanation: mountain[0] and mountain[2] can not be a peak because they are first and last elements of the array.\nmountain[1] also can not be a peak because it is not strictly greater than mountain[2].\nSo the answer is [].\n
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Example 2:

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\nInput: mountain = [1,4,3,8,5]\nOutput: [1,3]\nExplanation: mountain[0] and mountain[4] can not be a peak because they are first and last elements of the array.\nmountain[2] also can not be a peak because it is not strictly greater than mountain[3] and mountain[1].\nBut mountain [1] and mountain[3] are strictly greater than their neighboring elements.\nSo the answer is [1,3].\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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C# 10 with .NET 6 runtime

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Node.js 16.13.2.

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Python 3.10.

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