{ "data": { "question": { "questionId": "2047", "questionFrontendId": "1901", "boundTopicId": null, "title": "Find a Peak Element II", "titleSlug": "find-a-peak-element-ii", "content": "

A peak element in a 2D grid is an element that is strictly greater than all of its adjacent neighbors to the left, right, top, and bottom.

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Given a 0-indexed m x n matrix mat where no two adjacent cells are equal, find any peak element mat[i][j] and return the length 2 array [i,j].

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You may assume that the entire matrix is surrounded by an outer perimeter with the value -1 in each cell.

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You must write an algorithm that runs in O(m log(n)) or O(n log(m)) time.

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Example 1:

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\nInput: mat = [[1,4],[3,2]]\nOutput: [0,1]\nExplanation: Both 3 and 4 are peak elements so [1,0] and [0,1] are both acceptable answers.\n
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Example 2:

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\nInput: mat = [[10,20,15],[21,30,14],[7,16,32]]\nOutput: [1,1]\nExplanation: Both 30 and 32 are peak elements so [1,1] and [2,2] are both acceptable answers.\n
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Constraints:

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