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57 lines
3.1 KiB
HTML
57 lines
3.1 KiB
HTML
<p>You are given a <code>m x n</code> matrix <code>grid</code> consisting of <b>non-negative</b> integers where <code>grid[row][col]</code> represents the <strong>minimum</strong> time required to be able to visit the cell <code>(row, col)</code>, which means you can visit the cell <code>(row, col)</code> only when the time you visit it is greater than or equal to <code>grid[row][col]</code>.</p>
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<p>You are standing in the <strong>top-left</strong> cell of the matrix in the <code>0<sup>th</sup></code> second, and you must move to <strong>any</strong> adjacent cell in the four directions: up, down, left, and right. Each move you make takes 1 second.</p>
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<p>Return <em>the <strong>minimum</strong> time required in which you can visit the bottom-right cell of the matrix</em>. If you cannot visit the bottom-right cell, then return <code>-1</code>.</p>
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<p> </p>
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<p><strong class="example">Example 1:</strong></p>
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<p><img alt="" src="https://assets.leetcode.com/uploads/2023/02/14/yetgriddrawio-8.png" /></p>
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<pre>
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<strong>Input:</strong> grid = [[0,1,3,2],[5,1,2,5],[4,3,8,6]]
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<strong>Output:</strong> 7
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<strong>Explanation:</strong> One of the paths that we can take is the following:
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- at t = 0, we are on the cell (0,0).
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- at t = 1, we move to the cell (0,1). It is possible because grid[0][1] <= 1.
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- at t = 2, we move to the cell (1,1). It is possible because grid[1][1] <= 2.
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- at t = 3, we move to the cell (1,2). It is possible because grid[1][2] <= 3.
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- at t = 4, we move to the cell (1,1). It is possible because grid[1][1] <= 4.
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- at t = 5, we move to the cell (1,2). It is possible because grid[1][2] <= 5.
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- at t = 6, we move to the cell (1,3). It is possible because grid[1][3] <= 6.
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- at t = 7, we move to the cell (2,3). It is possible because grid[2][3] <= 7.
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The final time is 7. It can be shown that it is the minimum time possible.
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</pre>
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<p><strong class="example">Example 2:</strong></p>
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<p><img alt="" src="https://assets.leetcode.com/uploads/2023/02/14/yetgriddrawio-9.png" style="width: 151px; height: 151px;" /></p>
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<pre>
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<strong>Input:</strong> grid = [[0,2,4],[3,2,1],[1,0,4]]
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<strong>Output:</strong> -1
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<strong>Explanation:</strong> There is no path from the top left to the bottom-right cell.
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</pre>
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<p> </p>
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<p><strong>Constraints:</strong></p>
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<ul>
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<li><code>m == grid.length</code></li>
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<li><code>n == grid[i].length</code></li>
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<li><code>2 <= m, n <= 1000</code></li>
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<li><code>4 <= m * n <= 10<sup>5</sup></code></li>
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<li><code>0 <= grid[i][j] <= 10<sup>5</sup></code></li>
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<li><code>grid[0][0] == 0</code></li>
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</ul>
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<p> </p>
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