{ "data": { "question": { "questionId": "2914", "questionFrontendId": "2812", "boundTopicId": null, "title": "Find the Safest Path in a Grid", "titleSlug": "find-the-safest-path-in-a-grid", "content": "

You are given a 0-indexed 2D matrix grid of size n x n, where (r, c) represents:

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You are initially positioned at cell (0, 0). In one move, you can move to any adjacent cell in the grid, including cells containing thieves.

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The safeness factor of a path on the grid is defined as the minimum manhattan distance from any cell in the path to any thief in the grid.

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Return the maximum safeness factor of all paths leading to cell (n - 1, n - 1).

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An adjacent cell of cell (r, c), is one of the cells (r, c + 1), (r, c - 1), (r + 1, c) and (r - 1, c) if it exists.

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The Manhattan distance between two cells (a, b) and (x, y) is equal to |a - x| + |b - y|, where |val| denotes the absolute value of val.

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Example 1:

\n\"\"\n
\nInput: grid = [[1,0,0],[0,0,0],[0,0,1]]\nOutput: 0\nExplanation: All paths from (0, 0) to (n - 1, n - 1) go through the thieves in cells (0, 0) and (n - 1, n - 1).\n
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Example 2:

\n\"\"\n
\nInput: grid = [[0,0,1],[0,0,0],[0,0,0]]\nOutput: 2\nExplanation: The path depicted in the picture above has a safeness factor of 2 since:\n- The closest cell of the path to the thief at cell (0, 2) is cell (0, 0). The distance between them is | 0 - 0 | + | 0 - 2 | = 2.\nIt can be shown that there are no other paths with a higher safeness factor.\n
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Example 3:

\n\"\"\n
\nInput: grid = [[0,0,0,1],[0,0,0,0],[0,0,0,0],[1,0,0,0]]\nOutput: 2\nExplanation: The path depicted in the picture above has a safeness factor of 2 since:\n- The closest cell of the path to the thief at cell (0, 3) is cell (1, 2). The distance between them is | 0 - 1 | + | 3 - 2 | = 2.\n- The closest cell of the path to the thief at cell (3, 0) is cell (3, 2). The distance between them is | 3 - 3 | + | 0 - 2 | = 2.\nIt can be shown that there are no other paths with a higher safeness factor.\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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Python 2.7.12.

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For Map/TreeMap data structure, you may use sortedcontainers library.

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C# 10 with .NET 6 runtime

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Ruby 3.1

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Go 1.18

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Python 3.10.

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Dart 2.17.3

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