{ "data": { "question": { "questionId": "882", "questionFrontendId": "852", "boundTopicId": null, "title": "Peak Index in a Mountain Array", "titleSlug": "peak-index-in-a-mountain-array", "content": "

Let's call an array arr a mountain if the following properties hold:

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Given an integer array arr that is guaranteed to be a mountain, return any i such that arr[0] < arr[1] < ... arr[i - 1] < arr[i] > arr[i + 1] > ... > arr[arr.length - 1].

\n\n

 

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Example 1:

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\nInput: arr = [0,1,0]\nOutput: 1\n
\n\n

Example 2:

\n\n
\nInput: arr = [0,2,1,0]\nOutput: 1\n
\n\n

Example 3:

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\nInput: arr = [0,10,5,2]\nOutput: 1\n
\n\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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