{ "data": { "question": { "questionId": "1117", "questionFrontendId": "1162", "boundTopicId": null, "title": "As Far from Land as Possible", "titleSlug": "as-far-from-land-as-possible", "content": "

Given an n x n grid containing only values 0 and 1, where 0 represents water and 1 represents land, find a water cell such that its distance to the nearest land cell is maximized, and return the distance. If no land or water exists in the grid, return -1.

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The distance used in this problem is the Manhattan distance: the distance between two cells (x0, y0) and (x1, y1) is |x0 - x1| + |y0 - y1|.

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Example 1:

\n\"\"\n
\nInput: grid = [[1,0,1],[0,0,0],[1,0,1]]\nOutput: 2\nExplanation: The cell (1, 1) is as far as possible from all the land with distance 2.\n
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Example 2:

\n\"\"\n
\nInput: grid = [[1,0,0],[0,0,0],[0,0,0]]\nOutput: 4\nExplanation: The cell (2, 2) is as far as possible from all the land with distance 4.\n
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Constraints:

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